Combination of Substituted Cyclodextrin Compound and Activated Carbon

ABSTRACT

The invention is a composition that can prevent formation in, or scavenge undesirable organic materials from, a polymer matrix. The composition contains cyclodextrin and particles of activated carbon. The composition can scavenge thermal decomposition products that can be produced during melt processing of a polymer, contaminants inherent in a polymer, or other types of impurities from a polymer matrix that otherwise may elute into the air, a water supply, or an ingestible material such as a food, a drug, or a beverage. Other aspects of the invention are blends of the composition with polymeric materials, methods of making blends, articles containing the composition, and methods of making articles containing the composition.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority from provisional application Ser. No.60/890,707, filed Feb. 20, 2007, and which is incorporated herein byreference.

FIELD OF THE INVENTION

The invention relates to a composition that can prevent formation of orscavenge undesirable organics from contact with a polymer matrix. Theinvention relates to scavenging thermal decomposition products producedduring melt processing from contaminants inherent in the composition andimpurities from a polymer matrix that otherwise may elute into the air,a water supply, or an ingestible material such as a food, a drug, or abeverage. The invention is drawn to compositions for preventing therelease of or scavenging volatile organic components; blends of polymerswith the compositions of the invention; and articles made from thepolymers having the compositions of the invention. The invention isfurther drawn to methods of making the compositions; methods of makingthe blends; and methods of making the articles.

BACKGROUND OF THE INVENTION

Synthetic polymer resins are used for a vast array of applications. Insome applications, polymers can come into contact with or can be asource of undesirable organic materials that can be eluted into theatmosphere, a water supply, or an ingestible material inside a polymericpackage. These organic materials may be formed by degradation of thepolymer during processing, or may be the result of adding smallmolecules to the matrix, such as plasticizers or solvents. A polymermatrix may also absorb undesirable organic materials from externalsources, or allow these materials to diffuse into the polymer packagecontents. Additionally, the barrier properties of a polymer may cause abuildup of undesirable organic materials inside packaging when, forexample, foods inside begin to decay.

One industrially important polymer is polyethylene terephthalate (PET).PET packaging materials in the form of films, shaped containers,bottles, etc. have been known. Further, rigid, or semi-rigid,thermoplastic beverage containers have been made from preforms that arein turn molded from pellets or chips etc. Biaxially oriented blow moldedthermoformed polyester beverage containers are disclosed in J. Agranoff(Ed) Modern Plastics, Encyclopedia, Vol. 16, No. 10A, P. (84) pp.192-194. These beverage containers are typically made from a polyester,a product of a condensation polymerization. The polyester is typicallymade by reacting a dihydroxy compound and a diacid compound in acondensation reaction with a metallic catalyst. Dihydroxy compounds suchas ethylene glycol, 1,4-butane diol, 1,4-cyclohexane diol and other diolcan be copolymerized with an organic diacid compound or lower diesterthereof such diacid. Such diacidic reactants include terephthalic acid,2,6-naphthalene dicarboxylic acid, methyl diester thereof, etc. Thecondensation/polymerization reaction occurs between the dicarboxylicacid, or a dimethyl ester thereof and the glycol material in a heatdriven metal catalyzed reaction that releases water or methanol as areaction by-product leaving, a high molecular weight polyester material.Bulk resin is formed as a convenient flake, chip or pellet adapted forfuture thermal processing. Bulk polyester material can be injection blowmolded directly into a container. Alternately, the polyester can beformed into an intermediate preform that can then be introduced into ablow-molding machine. The polyester is heated and blown to anappropriate shape and volume for a beverage container. The preform canbe a single layer material, a bilayer or a multilayer preform.

Metallic catalysts are used to promote a polymerization reaction betweendiacid material and the dihydroxy compound. At the beginning of the meltphase, ethylene glycol, terephthalic acid, or ester thereof, andmetallic catalysts are added to the reactor vessel. Various catalystsare known in the art to be suitable for the transesterification step.Salts of organic acids with bivalent metals (e.g. manganese, zinc,cobalt or calcium acetate) are preferably used as—direct esterificationor trans-esterification catalysts, which in themselves also catalyze thepolycondensation reaction. Antimony, germanium and titanium compoundsare preferably used as polycondensate catalysts. Catalysts that may beused include organic and inorganic compounds of one or more metals aloneor in combination with the above-described antimony, also includinggermanium and titanium. Suitable forms of antimony can be used,including inorganic antimony oxides, and organic compounds of antimony,such as antimony acetate, antimony oxalate, antimony glycoxide, antimonybutoxide, and antimony dibutoxide. Antimony-containing compounds arecurrently in widespread commercial use as catalysts that provide adesirable combination of high reaction rate and low color formation.Titanium may be chosen from the group consisting of the followingorganic titanates and titanium complexes: titanium oxalate, titaniumacetate, titanium butylate, titanium benzoate, titanium isoproprylate,and potassium titanyl oxalate. Organic titanates are not generally usedin commercial production.

At the end of the melt phase, after polymerization is complete andmolecular weight is maximized, the product is pelletized. The pelletsare treated in solid-state polycondensation to increase intrinsicviscosity in order to obtain bottle resin of sufficient strength. Thecatalysts typically comprise metallic divalent or trivalent cations.

The treatment of polyester materials containing such catalysts canresult in byproduct formation. Such byproduct can comprise reactiveorganic materials such as an aldehyde material, commonly analyzed asacetaldehyde. The formation of acetaldehyde materials can cause off odoror off taste in the beverage and can provide a yellowish cast to theplastic at high concentrations. Polyester manufacturers have addedphosphorus-based additives as metal stabilizers to reduce acetaldehydeformation. Many attempts to reduce aldehyde formation have also causedproblems. Antimony present as Sb⁺¹, Sb⁺² and Sb⁺³ in the polyester ascatalyst residues from manufacture can be reduced to antimony metal,Sb⁰, by the additives used to prevent aldehyde formation or scavengesuch materials. Formation of metallic antimony can cause a gray or blackappearance to the plastic from the dispersed, finely divided metallicresidue.

The high molecular weight thermoplastic polyester can contain a largevariety of relatively low molecular weight compound, (i.e.) a molecularweight substantially less than 500 grams per mole as a result of thecatalytic mechanism discussed above or from other sources. Thesecompounds can be extractable into food, water or the beverage within thecontainer. These beverage extractable materials typically compriseimpurities in feed streams of the diol or diacid used in making thepolyester. Further, the extractable materials can comprise by-productsof the polymerization reaction, the preform molding process or thethermoforming blow molding process. The extractable materials cancomprise reaction byproduct materials including formaldehyde, formicacid, acetaldehyde, acetic acid, 1,4-dioxane, 2-methyl-1,3-dioxolane,and other organic reactive aldehyde, ketone and acid products. Further,the extractable materials can contain residual diester, diol or diacidmaterials including methanol, ethylene glycol, terephthalic acid,dimethyl terephthalic, 2,6-naphthalene dicarboxylic acid and esters orethers thereof. Relatively low molecular weight (compared to thepolyester resin) oligomeric linear or cyclic diesters, triesters orhigher esters made by reacting one mole of ethylene glycol with one moleof terephthalic acid may be present. These relatively low molecularoligomers can comprise two or more moles of diol combined with two ormore moles of diacid. Schiono, Journal of Polymer Science: PolymerChemistry Edition, Vol. 17, pp. 4123-4127 (1979), John Wiley & Sons,Inc. discusses the separation and identification of PET impuritiescomprising poly(ethylene terephthalate) oligomers by gel permeationchromatography. Bartl et al., “Supercritical Fluid Extraction andChromatography for the Determination of Oligomers and Poly(ethyleneterephthalate) Films”, Analytical Chemistry, Vol. 63, No. 20, Oct. 15,1991, pp. 2371-2377, discusses experimental supercritical fluidprocedures for separation and identification of a lower oligomerimpurity from polyethylene terephthalate films.

Foods or beverages containing these soluble/extractables derived fromthe container, can have a perceived off-taste, a changed taste or even,in some cases, reduced taste when consumed by a sensitive consumer. Theextractable compounds can add to or interfere with the perception ofeither an aroma note or a flavor note from the beverage material.Additionally, some substantial concern exists with respect to thetoxicity or carcinogenicity of any organic material that can beextracted into beverages for human consumption.

The technology relating to compositions used in the manufacture ofbeverage containers is rich and varied. In large part, the technology isrelated to coated and uncoated polyolefin containers and to coated anduncoated polyester that reduce the permeability of gasses such as carbondioxide and oxygen, thus increasing shelf life. The art also relates tomanufacturing methods and to bottle shape and bottom configuration. Deafet al., U.S. Pat. No. 5,330,808, teach the addition of a fluoroelastomerto a polyolefin bottle to introduce a glossy surface onto the bottle.Visioli et al., U.S. Pat. No. 5,350,788, teach methods for reducingodors in recycled plastics. Visioli et al. disclose the use of nitrogencompounds including polyalkylenimine and polyethylenimine to act as odorscavengers in polyethylene materials containing a large proportion ofrecycled polymer.

Wyeth et al., U.S. Pat. No. 3,733,309, show a blow molding machine thatforms a layer of polyester that is blown in a blow mold. Addleman, U.S.Pat. No. 4,127,633, teaches polyethylene terephthalate preforms whichare heated and coated with a polyvinylidene chloride copolymer latexthat forms a vapor or gas barrier. Halek et al., U.S. Pat. No.4,223,128, teach a process for preparing polyethylene terephthalatepolymers useful in beverage containers. Bonnebat et al., U.S. Pat. No.4,385,089, teach a process for preparing biaxially oriented, hollowthermoplastic shaped articles in bottles using a biaxial draw and blowmolding technique. A preform is blow molded and then maintained incontact with hot walls of a mold to at least partially reduce internalresidual stresses in the preform. The preform can be cooled and thenblown to the proper size in a second blow molding operation. Gartland etal., U.S. Pat. No. 4,463,121, teach a polyethylene terephthalatepolyolefin alloy having increased impact resistance, high temperature,dimensional stability and improved mold release. Ryder, U.S. Pat. No.4,473,515, teaches an improved injection blow molding apparatus andmethod. In the method, a parison or preform is formed on a cooled rodfrom hot thermoplastic material. The preform is cooled and thentransformed to a blow molding position. The parison is then stretched,biaxially oriented, cooled and removed from the device. Nilsson, U.S.Pat. No. 4,381,277, teaches a method for manufacturing a thermoplasticcontainer comprising a laminated thermoplastic film from a preform. Thepreform has a thermoplastic layer and a barrier layer which issufficiently transformed from a preformed shape and formed to acontainer. Jakobsen et al., U.S. Pat. No. 4,374,878, teach a tubularpreform used to produce a container. The preform is converted into abottle. Motill, U.S. Pat. No. 4,368,825; Howard Jr., U.S. Pat. No.4,850,494; Chang, U.S. Pat. No. 4,342,398; Beck, U.S. Pat. No.4,780,257; Krishnakumar et al., U.S. Pat. No. 4,334,627; Snyder et al.,U.S. Pat. No. 4,318,489; and Krishnakumar et al., U.S. Pat. No.4,108,324, each teach plastic containers or bottles having preferredshapes or self-supporting bottom configurations. Hirata, U.S. Pat. No.4,370,368, teaches a plastic bottle comprising a thermoplasticcomprising vinylidene chloride and an acrylic monomer and other vinylmonomers to obtain improved oxygen, moisture or water vapor barrierproperties. The bottle can be made by casting aqueous latex in a bottlemold, drying the cast latex or coating a preform with the aqueous latexprior to bottle formation. Kuhfuss et al., U.S. Pat. No. 4,459,400,teach a poly(ester-amid) composition useful in a variety of applicationsincluding packaging materials. Maruhashi et al., U.S. Pat. No.4,393,106, teach laminated or plastic containers and methods formanufacturing the container. The laminate comprises a moldable plasticmaterial in a coating layer. Smith et al., U.S. Pat. No. 4,482,586,teach a multilayer of polyester article having good oxygen and carbondioxide barrier properties containing a polyisophthalate polymer.Walles, U.S. Pat. Nos. 3,740,258 and 4,615,914, teach that plasticcontainers can be treated, to improve barrier properties to the passageof organic materials and gases, such as oxygen, by sulfonation of theplastic. Rule et al., U.S. Pat. No. 6,274,212, teaches scavengingacetaldehyde using scavenging compounds having adjacent to heteroatomscontaining functional groups that can form five or six member bridgethrough condensation with acetaldehyde. Al-Malaika PCT WO 2000/66659 andWeigner et al., PCT WO 2001/00724 teach the use of polyol materials asacetaldehyde scavengers.

Further, we are aware that the polyester has been developed andformulated to have high burst resistance to resist pressure exerted onthe walls of the container by carbonated beverages. Further, somesubstantial work has been done to improve the resistance of thepolyester material to stress cracking during manufacturing, filling andstorage. Modifications to the polyester material or formulation used insuch an application should not compromise the structural integrity ofthe formed container.

Beverage manufacturers have long searched for improved barrier material.In larger part, this research effort was directed to carbon dioxide(CO₂) barriers, oxygen (O₂) barriers and water vapor (H₂O) barriers.More recently, original bottle manufacturers have had a significantincrease in sensitivity to the presence of beverage extractable orbeverage soluble materials in the resin or container. This work has beento improve the bulk plastic with polymer coatings or polymer laminatesof less permeable polymer to decrease permeability.

Even with this substantial body of technology, substantial need hasarisen to develop biaxially oriented thermoplastic polymer materials forbeverage containers that can substantially reduce the elution ofreactive organic materials into a food or beverage in the container orreduce the passage of permeants in the extractable materials that passinto beverages intended for human consumption.

Stabilization of polyester resins and absorption of reactive organicssuch as acetaldehyde have drawn significant attention. Proposals forresolving the problem have been posed. One proposal involves usingactive stabilizers including phosphor compounds and nitrogenheterocycles as shown in, for example, WO 9744376, EP 26713 and U.S.Pat. No. 5,874,517 and JP 57049620. Another proposal, which has receivedgreat attention, includes solid state polycondensation (SSP) processing.The materials after the second polymerization stage are treated withwater or aliphatic alcohols to reduce residuals by decomposition.Acetaldehyde may also be scavenged with reactive chemical materialsincluding low molecular weight partially aromatic polyamides based onxylylene diamine materials and low molecular weight aliphaticpolyamides.

See, for example, U.S. Pat. Nos. 5,258,233, 6,042,908, and EuropeanPatent No. 0 714 832, commercial polyamides see WO9701427, polyethyleneimine see U.S. Pat. No. 5,362,784, polyamides of terephthalic acid seeWO9728218 and the use of inorganic absorbents such as zeolites, see U.S.Pat. No. 4,391,971.

Bagrodia, U.S. Pat. No. 6,042,908 uses polyester/polyamide blends toimprove flavor of ozonated water. Hallock, U.S. Pat. No. 6,007,885,teaches oxygen-scavenging compositions in polymer materials. Ebner, U.S.Pat. No. 5,977,212, also teaches oxygen-scavenging materials inpolymers. Rooney, U.S. Pat. No. 5,958,254, teaches oxygen scavengerswithout transitional catalysts for polymer materials. Speer, U.S. Pat.No. 5,942,297, teaches broad product absorbance to be combined withoxygen scavengers in polymer systems. Palomo, U.S. Pat. No. 5,814,714,teaches blended mono-olefin/polyene interpolymers. Lastly, Visioli, U.S.Pat. No. 5,350,788, teaches method for reducing odors in recycledplastics.

Wood, et al. U.S. Pat. Nos. 5,837,339; 5,882,565; 5,883,161; 6,136,354and other applications pending, teach the use of substitutedcyclodextrin in polyester for barrier properties. Wood et al., U.S. Pat.No. 7,166,671 teach the use of a polymer grafted with cyclodextrin inpolyolefins for barrier properties.

Activated carbons (CAS No. 7440-44-0) are porous synthetic solidmaterials that are commonly used in a wide variety of applications forpurification, decolorization, and odor removal of gases and liquids.Activated carbon and in particular acid-washed activated carbon is ahighly desirable material to entrain in a polymeric matrix for thepurpose of scavenging undesirable organic molecules in gas and liquidphases, such as compounds formed during polymer processing as theproducts of thermal decomposition. In barrier layer applications, theinclusion of carbon would be desirable for the purpose of includingscavenging properties for materials that would otherwise diffuse throughthe polymer matrix.

However, it is broadly understood that carbon particles are often notused in transparent polymer layers since they can be highly lightscattering and can typically provide a black or gray cast to polymerlayers. If large enough, individual particles can also be observed whenthe carbon is present in a clear medium, such as a water-white solventor polymer matrix. Many ink formulations, for example, employ carbonblack as the black pigment of choice. Automobile tires typically employa large percentage of carbon black. The light scattering properties ofcarbon, while desirable in some applications, are not desirable where,for example, a clear, water-white, or an opaque or translucent whitepolymer matrix is desired.

Further, the presence of any particular particle in a polymer matrix canbe deleterious to physical properties. Particles can have intimate andstrong adhesion to the surrounding polymer matrix. The tensile strengthof the polymer matrix typically increases, yet the elongation at breakis decreased. Even where matrix-filler interactions are favorable, theresulting physical properties often reflect a lower strain at break thanthe matrix inherently possesses without the filler due to increasedstress per unit of strain. This may be undesirable in certainapplications, especially where the tensile properties of the polymerhave been optimized without other materials being present. Further, ithas been observed that the use of very small amounts of fillerparticles, such as 0.1 volume fraction or less of the total composition,is actually deleterious to the tensile strength and impact strength, inaddition to lowering the elongation at break, where adhesion of thefiller to the matrix is good. (For a discussion of this phenomenon seeNielsen, L. E., Simple Theory of Stress-Strain Properties of FilledPolymers, J. Appl. Pol. Sci. 10, 97-103 (1966).)

Where adhesion between the particle and the polymer matrix is minimal,elongation and other tensile properties of the polymer matrix may remainlargely the same as the matrix without filler. However, as the matrix isstretched, the lack of adhesion between the particle and the polymerallows the filler to distort and concentrate the stress field bypropagating a void around the particle in the direction of the stress.As the polymer breaks the void travels from one filler particle to thenext and causes ultimate failure of the polymer.

Variations on these stress-strain behaviors can occur in the melt aswell. Thus, a particle in a polymer melt may cause visual defects in thematrix even when particles are so small or used in such a smallconcentration as to be invisible to the naked eye. Voids may form in thedirection of stress as a polymer is biaxially oriented, blowmolded,spun, or some other process that incurs stress to the polymer melt.These voids may be visible to the unassisted human eye as streaks,bubbles, and the like. The visible defects alone may be undesirable, orthe defects may undesirable because they constitute weak spots in thepolymer matrix, such that the physical properties of the polymer may becompromised in subsequent applications. For example, burst strength ofthe resulting polymer matrix may in insufficient because the defectscause failure of the matrix under relatively low pressures compared tothe polymer without defects. Impact strength, tensile strength, andelongation at break can be similarly affected and may render a polymermatrix unusable for a given application.

Further, many fillers, including carbon, will tend to increase opacityof the otherwise clear, water white polyester. Inclusion of carbon as afiller will typically impart a gray cast, which is undesirable forcertain applications e.g. beverage container bottles. However, Otto etal., U.S. Pat. No. 6,358,578, disclose the use of activated carbon inpolyester matrixes, where an average particle size of 2 μm or less,preferably 500 nm or less, may be incorporated into polyester withoutproducing discoloration. In that application, carbon particles arecocatalysts in transesterification reactions of the polyester. Thecarbon particles are milled prior to use in the polyester formulation inorder to reduce the particle size. Physical properties of the resultingmatrixes are not disclosed, nor are the presence of any structuraldefects or visual defects aside from discoloration.

Inclusion of activated carbon with cyclodextrin is found in othercompositions of the prior art. For example, Nakazima, U.S. Pat. No.5,001,176 disclose polyolefin compositions having a cyclodextrin and adibenzylidenesorbitol-type compound. Carbon black is mentioned as anoptional additive, but is not claimed. Andrews et al., U.S. Pat. No.6,790,499 disclose a polyester composition having a polyhydric alcohol,which can be cyclodextrin. Eisenhart et al., U.S. Pat. No. 5,137,571disclose the use of cyclodextrin as reversibly bound to water solublepolymers for the purpose of reversibly viscosifying aqueous systems. Aformulation having carbon black is disclosed, but is not claimed.Nakamura et al., U.S. Pat. No. 5,854,320 disclose an ink compositioncontaining cyclodextrin. Carbon black is disclosed in the specificationas a pigment for a blank ink formulation. Similarly, Miyamoto et al.,U.S. Pat. No. 6,827,767 and Suzuki et al., U.S. Pat. No. 6,849,111disclose ink formulations having cyclodextrin and carbon black as acolorant. Woo et al., U.S. Pat. No. 6,833,342 disclose a non-polymericdeodorant composition having cyclodextrin, useful for carpet cleaningapplications. Carbon is disclosed in a long list of optional potentialadditives, but is not claimed.

BRIEF DISCUSSION OF THE INVENTION

We have found a unique class of additives for blending with polymersthat can act to prevent absorption, generation of, formation of orscavenge undesirable organics form the polymer materials. Alternatively,the additive can act as a barrier layer to prevent diffusion of organicsmall molecules through a polymer matrix. Finally, the additive canscavenge the byproducts of thermal processing, where degradation ofmaterials can result in undesirable small molecule VOCs.

We have found that the combination of cyclodextrin and activated carbonparticles is a desirable additive composition for inclusion into variouspolymer matrices. Surprisingly, the inclusion of carbon particles ishighly beneficial, even when present at very low concentrations, whenadded along with cyclodextrin to aid and improve the scavengingproperties of the cyclodextrin by increasing the amount of cyclodextrinfree of a complex. By using low concentrations of small particles ofactivated carbon, we have found that the light scattering propertiesassociated with carbon are not observed even for applications requiringa transparent and water-white finished product. Further, by using lowconcentrations of small particle size activated carbon, physicalproperties of the finished articles having both cyclodextrin and carbonparticles is not significantly changed; the polymer matrix hassubstantially the same tensile strength, elongation at break, etc. asthe polymer without the carbon particles.

The activated carbon complements the scavenging properties ofcyclodextrin, enhancing scavenging of organic compounds such as organicacids in addition to the aldehyde scavenging properties of thecyclodextrin compound. The scavenging of organic acids is particularlybeneficial because in subsequent thermal processing of polymerscontaining cyclodextrin, organic acids (e.g., formic, acetic andpropanoic) can dehydrate the α-D-glucopyranose units within thecyclodextrin ring causing off-yelow color. Organic acids are a commonimpurity in many industrial grade resins, which previously presented aproblem when the scavenging properties of cyclodextrin were desirablyintroduced into a thermoplastic article. This problem is obviated by theacid scavenging properties of the polymer additives of the presentinvention. Further, aldehyde scavenging is itself increased when bothcyclodextrin compound and activated carbon are incorporated into apolymer matrix when compared to the scavenging of aldehyde bycyclodextrin compound alone.

The driving force for inclusion is mainly the substitution of thepolar-apolar interaction between the apolar CD cavity and polar water,or apolar potential guest chemical and water. The driving force forinclusion is also apolar-apolar interactions between the guest and CDcavity. While this initial equilibrium to form the complex is very rapid(often within minutes), the final equilibrium can take much longer toreach. An equilibrium is established between dissociated and associatedspecies, and is expressed by the complex stability constant, K_(a)

CD + D ⇆ CD ⋅ D$K_{1\text{:}1} = \frac{\lbrack {{CD} \cdot D} \rbrack}{\lbrack{CD}\rbrack\lbrack D\rbrack}$

The guest can be displaced from the CD cavity under certain conditionsand dissociation of the inclusion complex is a relatively rapid process.Different cyclodextrin pore size and derivative modification allows somecontrol of the complex equilibrium. If the displaced guest is unable tofind a CD molecules to reform the complex, the guest chemical can existsin the free volume of the polymer matrix. Because the equilibrium isdynamic, it further creates an opportunity for activated carbon toscavenge residual resin contaminants shifting the equilibrium to theright. Typical contaminant concentration in the polymer matrix are inthe low parts per million or high parts per billion which favors andequilibrium shift to the right.

The additive compositions of the invention comprise, in their simplestform, a cyclodextrin and an activated carbon particle. Additivecompositions may be formed by adding carbon to cyclodextrin; theaddition is done either by dry-blending or in a solvent. The specificapplication and manufacturing process will dictate the specific solvent.The cyclodextrin may be an α-, β-, or γ-cyclodextrin or a mixturethereof. Preferably, the cyclodextrin compound utilized in thetechnology of the invention involves a substituted β- or α-cyclodextrin.Preferably the substituent on the cyclodextrin is methyl or acetyl.Preferred cyclodextrin materials and their use in polymer matrixes aredescribed in Wood et al., U.S. Pat. Nos. 5,837,339; 5,882,565;5,883,161; and 6,136,354; 6,709,746; 6,878,457; 6,974,603; and7,018,712, which are incorporated herein by reference in their entirety.

Another preferred composition comprises cyclodextrin integrallyincorporated into the backbone of a polymer or pendant on a polymer.Nonlimiting examples of such materials include Wood, et al., U.S. Pat.No. 7,166,671 which discloses a grafting reaction wherein cyclodextrinis reacted with e.g. maleic anhydride groups present along a polyolefinbackbone. Iwao et al., JP 59227906 describe the reaction of afunctionalized cyclodextrin with a high molecular weight carboxy estergroup containing material. Masanobu, JP 05051402 describes the reactionof cyclodextrin with a halogen containing or other reactive compounds toform a cyclodextrin copolymer. Sidhu, et al., WO 93/05084 disclose anaddition polymer containing cyclodextrin, wherein the cyclodextrin isreacted as β-cyclodextrinacrylate, among others. Szejtli, et al., U.S.Pat. Nos. 4,547,572 and 4,274,985 disclose various copolymers ofcyclodextrin, including copolymers with epichlorohydrin, cellulosehaving pendant cyclodextrin groups attached by means of alkylene oxidepolymers containing cyclodextrin, and polyvinyl alcohol copolymers. AndRohrbach, EP 0454910A1 disclose the crosslinking reaction ofpolyisocyanates with cyclodextrins. U.S. Patent Publication No.2004/0110901, JP 59227906, JP 05051402, WO 93/05084, U.S. Pat. No.4,547,572, U.S. Pat. No. 4,274,985, and EP 0454910A1 are incorporatedherein by reference in their entirety. The current inventioncontemplates the use of any of these polymers in conjunction withactivated carbon for incorporation into compositions, masterbatches, andfinal articles of the invention using any of the processes describedherein as well as techniques that are known in the art of polymerprocessing.

Another preferred embodiment of the present invention comprisescyclodextrin attached to the surface of an article by coating thearticle with cyclodextrin and subjecting the coated article to anelectron beam. This process is described in Yahiaoui et al., U.S. Pat.No. 6,613,703, which is incorporated herein by reference in itsentirety. The current invention contemplates the treatment of articlescoated with cyclodextrin in conjunction with activated carbon forelectron beam treatment of final articles of the invention.

The cyclodextrin can be dissolved in solvent such that the concentrationof cyclodextrin compound is from about 1.8 to about 60% by weight. Thesolution is then contacted with activated carbon such that theconcentration of carbon is from about 0.001 to about 1.0% by weight.Preferably, the carbon has a pH in water from about 6 to 10 to avoidyellowing of the polymer matrixes in which the particles areincorporated. The ratio of carbon particles to cyclodextrin groups inthe additive compositions of the invention can range from 1:1,000,000 to20:1. Preferably the ratio of carbon to cyclodextrin is 1:2 to 1:40,000.The cyclodextrin and the carbon are mutually exclusive and do not appearto substantially penetrate into the interior pore or space of thecyclodextrin or into the porous nature of the carbon particle.

The solution can further be filtered using pore sizes of about 10 nm toabout 100 μm. Using this means to control particle size, the activatedcarbon does not discolor the polymer matrix, a property commonlyassociated with carbon as a filler material. Alternatively, the solutioncan be centrifuged at about 500 to about 1000 rpm to remove largerparticles. After solvent addition and filtration or centrifugation, theadditive compositions may be dried prior to incorporating the additivecomposition to a masterbatch or final article of the present invention.

In some embodiments of the present invention, no solvents are employedand no filtration performed on the additive compositions. In theseembodiments, a powder comprising the cyclodextrin and carbon can beadmixed. The resulting powder blend can be added directly to anextrusion apparatus, where can be blended into a thermoplastic polymer.It is an advantage of these embodiments that no special milling or otherpreparations need be taken in order to provide the small particle sizesof carbon required to prevent large, visible particles from ending up inthe final articles of the invention. Because of the high shearencountered in an extruder, especially where twin screw extrusion isemployed, carbon with an average particle size of up to 100 μm may beemployed as an additive. After incorporation by extrusion, the finalparticle size will be 10 μm or less.

The additive compositions may also be dispersed or dissolved in an oilfor the purpose of delivering the additive composition to a masterbatchor a final article of the invention. Suitable oils includepolyalphaolefin, paraffinic, aromatic, or naphthenic extender oils aswell as silicone based oils. Such materials can be chosen to plasticizethe polymer matrix but must function to at least suitably deliver theadditive composition to a polymer matrix either in a single phase, i.e.a solution, or more than one phase, i.e. a dispersion or an emulsion.

In some embodiments of the present invention, a masterbatch having ahigh concentration of cyclodextrin and carbon in a thermoplastic resincan be formed. The masterbatch can advantageously be stored and used ina later process whereby the masterbatch is added to a polymer resinhaving no cyclodextrin or carbon. Preferably the addition is at amasterbatch-to-resin ratio of 1:1 to about 1:40, and is advantageouslytailored to arrive at a desirable final concentration of cyclodextrinand carbon that depends on the targeted application. The masterbatch canbe made by addition of an additive composition of the invention to athermoplastic resin in an extruder. The additive composition may bedelivered as a powder or in oil. After blending, the treatedthermoplastic masterbatch resin is preferably pelletized for ease ofstorage. The masterbatch may also be made by surface coating chips orpellets of a thermoplastic resin with a solution having cyclodextrin andcarbon and applying the solution using various spray coating apparatusknown in the art of seed coating (e.g., fluidized beds, tumblingfluidized beds, rotary disk and rotating drum) and drying the pellets toprovide a surface treated pellet or chip.

Masterbatches of the present invention contain cyclodextrin at about 100to about 150,000 parts by weight per one million parts by weight of themasterbatch composition, more preferably about 100 to about 80,000 partsby weight per one million parts by weight of the masterbatchcomposition. The masterbatches contain carbon particles at about 0.005to about 5000 parts by weight of per one million parts by weight of themasterbatch composition, more preferably about 0.05 to about 2000 partsby weight per one million parts by weight of the masterbatchcomposition. The ratio of carbon particles to cyclodextrin groups in themasterbatches of the invention can range from 1:1,000,000 to 20:1.Preferably the ratio of carbon to cyclodextrin is 1:2 to 1:40,000.

Articles having cyclodextrin and carbon can be formed by by blendingmasterbatches having a relatively high proportion of cyclodextrin andcarbon with untreated thermoplastic resin, and forming an article fromthe blend. Alternatively, an article can be made by extrusion blendingan additive composition of the invention into a thermoplastic resin atthe desired concentration. Articles of the invention may be formed usingany commonly employed technique. Thermal processing is the preferredmethod to form articles of the invention. Thermal processing may becarried out by extrusion, coextrusion, profile extrusion, injectionmolding, blow molding, injection blow molding, electrospinning;spunbonding, meltblowing, uniaxial or biaxial orientation, orcombinations thereof.

Additional materials may be incorporated into compositions containingcyclodextrin plus carbon particles. These materials may be incorporatedinto an additive composition, a masterbatch, or a final article of thepresent invention, depending on ease of incorporation and efficiency.Some nonlimiting examples of additional materials that may beincorporated include dyes, pigments, antioxidants, UV stabilizers,thermal stabilizers, bacteriocides, fungicides, fragrances,plasticizers, or tackifiers. These materials may be incorporated into apolymer matrix of the invention using any means known to the skilledartisan.

Preferably, the finished articles of the invention have 2000 ppm or lessof activated carbon, more preferably about 0.001 to about 500 ppm, andmost preferably 0.05 to 100 ppm of activated carbon particles based onthe weight of the article. Preferably, the finished articles of theinvention have about 10 to about 50,000 ppm of cyclodextrin, preferably100 to 25,000 ppm cyclodextrin based on the weight of the finishedarticle. The ratio of carbon particles to cyclodextrin groups in thearticles of the invention can range from 1:1,000,000 to 20:1. Preferablythe ratio of carbon to cyclodextrin is 1:2 to 1:40,000.

Notably, the activated carbon particles of the invention can range insize from 10 nm to 100 microns in the additive composition or themasterbatch compositions. It is contemplated that many embodiments ofthe invention will employ extrusion processing of the polymer matrixeshaving the additive compositions of the invention; where this is true,the particle size of the carbon in the additive composition or themasterbatch may be relatively large, e.g. 100 microns. It iscontemplated that extrusion processing of polymers having the additivecompositions of the invention causes large particles of carbon to beground to smaller sizes due to the physical kneading, shearing, andmixing that takes place in a typical extrusion operation, especiallytwin-screw extrusion. Thus, the particle size of carbon in either theadditive composition or in the masterbatch may be in the upper part ofthe 10 nm to 100 micron range.

In the final articles of the invention, however, it is preferable thatthe particle size of the activated carbon be no more than 1 micron,preferably 10 nm to 1 micron, more preferably 10 nm to 750 nm, stillmore preferably 10 nm to 500 nm, still more preferably 10 nm to 350 nm,still more preferably 10 nm to 250 nm, and most preferably 10 nm to 100nm. Such carbon particles provide sufficient pore volume to effectivelyact in concert with cyclodextrin to scavenge undesirable compounds frompolymer matrixes while having a small enough particle size that the userof a final article detects no gray cast and sees no individualparticles.

The final articles of the invention may be made using a variety oftechniques. In some embodiments, the final articles may be formed byadding the additive composition of the invention directly to anuntreated polymer, and blending the two components before forming thefinal article. The additive composition may be delivered to the polymermatrix in a solvent or by melt blending, for example in an extruder. Theadditive compositions may be added to the polymer matrix as a powder, ina solvent, or in oil. Oil may be beneficially used to deliver theadditive composition to the polymer matrix in melt blending, forexample, as a plasticizer. Delivery of the additive composition in asolvent is most preferably used where solvent blending of the polymerand additive composition is contemplated. Blending is most preferablycarried out using a twin screw extruder so as to achieve a uniformlyblended final article composition.

The final articles of the invention are preferably made by melt blendingof treated and untreated polymeric chips, wherein a treated polymericchips are masterbatch materials as described above. Thus, a masterbatchchip having relative high levels of cyclodextrin and carbon can be meltblended with a second chip not having any of the additive composition,at a ratio such that the desired levels of cyclodextrin and carbon arerealized after the two materials are blended together. The masterbatchchip may have been melt processed to blend the additive compositions ofthe invention therein, or the masterbatch chip may be surface coatedwith the additive composition. The melt blending may be carried outusing any conventional melt blending technique, though it is preferablyto employ twin screw extrusion to achieve a uniformly blended finalarticle.

After blending in the additive composition, the final articles of theinvention are formed using any known technique to shape and form apolymeric composition. For example, meltblowing of the compositions maybe carried out to form a fiber. Other techniques to form fibers may beused, such as electrospinning; spunbonding, meltblowing, or combinationsthereof. Additionally, the fibers may be formed as bicomponent fibers,wherein at least one component comprises cyclodextrin and activatedcarbon particles.

During extrusion operations where the additive composition of theinvention is included, the cyclodextrin compound and activated carbonmixes with the melt polymer at high temperature during a set residencetime. At the temperature of the melt extrusion, the cyclodextrincompound reacts with, complexes or associates with the metallic catalystresidues and prevents the production of catalytically generated reactiveorganic compounds, including aldehyde materials such as acetaldehyde.The activated carbon provides a further means of scavenging residualorganic compounds, both in the melt and after the formed article iscooled.

Surprisingly, the activated carbon may be included with the cyclodextrincompound and subsequently melt processed to provide a clear andwater-white finished molded polyester article, i.e. free of gray colorcommonly associated with activated carbon. The cyclodextrin compound andthe activated carbon can also react with and/or scavenge volatilereactive materials such as acetaldehyde or organic acids that arepresent in the resin or that are formed during melt processing. Apreform or blow molding residence time is selected that results ineffective aldehyde concentration reduction but without cyclodextrin orpolymer degradation. Such a reduction in aldehyde concentration reducesor eliminates major off-odors and off-flavors in the thermoplasticpolymer.

Also surprisingly, we have found that the inclusion of activated carbonparticles, when entrained in the polymer matrix in the manner describedherein, do not result in any deleterious effects with respect to thephysical properties of the polymeric matrix such as burst strength,elongation, or stress at break.

The final article may be a preform which is subsequently molded to forma final article. Such processing is preferably carried out when thefinal article is a three-dimensional shape such as a bottle, a cap, aclosure, or a container formed from a polyester. The final article mayalso be a thick member which is subsequently stretched to form a thinfilm, such as by uniaxial or biaxial stretching to form a thin film froma thick film.

The final articles of the invention may be in any form where a polymermay be used. Thus, the final article of the invention may be an entityunto itself, such as a nonwoven filter, a bottle, or a windowpane.Alternatively, the final article may be a portion of an overallconstruction, for example, a nonwoven cover for an absorbent article, asingle layer in a multilayer film construction, or a surface coating ona large article.

Nonlimiting examples of final articles include a container, a closure, afilm, a coextruded film, a sheet, a liner, a semi-rigid member, a rigidmember, a shaped member, a molded member, an embossed member, a porousmember, a fiber, a yarn, a nonwoven fabric, a woven fabric, a coating onan article, a thin layer on top of an article, a thick layer on top ofan article, a barrier layer, an injection molded article, a blow moldedarticle, a rotomolded article, masterbatch pellets, an open-celled foam,a closed-cell foam, an adhesive article, an absorbent article, or aportion or a combination thereof.

A first aspect of the invention comprises a mixture of cyclodextrin andcarbon particles as additive compositions. The cyclodextrin may be α, β,or γ-cyclodextrin. The cyclodextrin may be unsubstituted, substituted bya substituent such as methyl or acetyl, or may be covalently bound to apolymer. Where covalently bound to a polymer, the cyclodextrin may beintegral to the polymer backbone, such as by reacting two hydroxylgroups of cyclodextrin with a diisocyanate to form a polyurethane, or bycondensing cyclodextrin with a diacid to form a polyester.Alternatively, the cyclodextrin may be pendantly grafted to the polymer,such as by reacting a hydroxyl group of the cyclodextrin with a glycidylgroup or an anhydride group present in the polymer backbone. Theadditive composition may be in powder form or may be in solvent or in anoil.

A second aspect of the invention is a method of making the additivecompositions of the invention. The method may involve simply blendingthe two materials, blending them in solvent, blending in solventfollowed by filtration and optionally removing the solvent afterfiltration, or extrusion blending of the cyclodextrin and carbon with areactive polymer to graft the cyclodextrin to the polymer backbone.

A third aspect of the invention is a masterbatch pellet or chip having athermoplastic polyester material and a relatively concentrated level ofcyclodextrin and carbon. These high-concentration masterbatches aresubsequently used in making a final article. The masterbatch pellet orchip can comprise a coated layer of the additive composition of theinvention wherein the additive composition resides substantially on theexterior of the pellet or chip. Alternatively, the pellet or chip may bethe result of melt blending, such as in an extruder, to incorporate thecyclodextrin and carbon. In these embodiments the additive compositionwill be substantially dispersed throughout the thermoplastic pellet orchip.

A fourth aspect of the invention is a method of making the masterbatchpellets or chips. They may be made by coating and drying preformedthermoplastic pellets or chips. Or the masterbatch pellets or chips maybe melt blended, as in an extruder. In the latter case, themasterbatching method may also result in the covalent grafting ofcyclodextrin with a thermoplastic polymer having a reactive site forgrafting, such as an anhydride, chloride, or epoxy group pendant to thepolymer chain.

A fourth aspect of the invention comprises a thermoplastic beveragecontainer having the metal catalyst scavenger property and a volatileorganic barrier property that results from the manufacture of thebeverage container from the preform of the invention.

A fifth aspect of the invention comprises a final article comprising thedesired endpoint levels of both carbon and cyclodextrin, wherein thecyclodextrin is either substituted with one or more moieties, or iscovalently bonded to a polymer, or both. Also, in the final article, thecarbon particle size is preferably no more than 500 nm in order toensure that the particles are not visible in a white or clear polymermatrix, whereas in a masterbatch or additive composition it is notundesirable to have larger particles sizes. A wide range of finalarticles are envisioned, limited only by the bounds of all the generallyuseful shapes of thermoplastic polymers known in the art.

A sixth aspect of the invention is a method of making the final articlehaving the desired endpoint levels and particle sizes of carbon andcyclodextrin. Generally, processing methods known in the art can beemployed. The final articles may be made by blending masterbatch pelletsor chips with a proportion of thermoplastic polymer pellets or chips ina thermal blending process such as extrusion. It may also be made byblending the additive compositions of the invention directly into amolten polymer, such as by addition during extrusion. In the latterapplication, the additive composition may be introduced as a powder orin oil. In a final step, the final articles are formed into a finalshape. Such forming is limited only by the known art to shape polymers.Fine fibers and I-beams can be final articles of the present invention,as can many articles in between.

In the fifth and sixth aspects of the invention, the use of the purifiedcyclodextrin material having entrained activated carbon particles canresult in a clear, substantially water white polymer matrix havinglittle or no organic material to produce off odors or off flavors in thefood material within a container formed from the polymer. Further, thepolyester matrix suffers no structural defects of the type that oftenarise when particles are incorporated into a polymer matrix which issubsequently subjected to high strain, such as biaxial orientation orblow molding. Further, the barrier and scavenging properties imparted bythe use of a cyclodextrin compound in conjunction with particles ofactivated carbon are superior to those found in the prior art.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of cyclodextrin rings, showing the poresizes of α, β, and γ-cyclodextrin.

FIG. 2 is a side view of a substantially transparent two-litercarbonated beverage container comprising a composition of the invention.

FIG. 3 is an absorbent food pad having at least one layer comprising acomposition of the invention.

FIG. 4 is a diagram showing a fuel tank constructed of thermoplasticlayers, wherein at least one layer comprises a composition of theinvention.

FIG. 5 is carbon particle distribution in 35 wt.-% methyl β-cyclodextrinsolution centrifuged at 750 rpm for 30 minutes.

FIG. 6 is carbon particle distribution in Emery 3004 oil centrifuged at750 rpm for 30 minutes.

FIG. 7 is a gas chromatograph SPME headspace chromatogram of a 35 wt.-%methyl β cyclodextrin solution, dried to remove water, and heated to290° C. for 2 minutes.

FIG. 8 is a gas chromatograph SPME headspace chromatogram of a 35 wt.-%methyl β-cyclodextrin solution containing 0.1 wt % activated carbonbased on weight of cyclodextrin, dried to remove water, and then heatedto 290° C. for 2 minutes.

FIG. 9 is a visible wavelength scan of injection molded polyestercontaining 750 ppm methyl β-cyclodextrin, and injection molded polyestercontaining 750 ppm methyl β-cyclodextrin with 1.5 ppm coconut activatedcarbon.

DETAILED DISCUSSION OF THE INVENTION

We have found that the scavenging properties of many polymeric materialscan be substantially improved using a substituted cyclodextrin compoundin conjunction with an amount of activated carbon at a concentrationthat can prevent the formation of an organic material such as analdehyde, or scavenge formed organic material. We have further foundthat using a purified cyclodextrin material and an acid-washed carbon ispreferred for polyester processing. We have further found that aconcentration range of cyclodextrin compound in solution is preferredfor contact with activated carbon. We have further found that apreferred degree of substitution, concentration of substitutedcyclodextrin, particle size of activated carbon, concentration ofactivated carbon particles, and processing conditions produces ahigh-quality polyester matrix. We have found that combining a modifiedcyclodextrin material and activated carbon particles from the abovementioned purification process with the polymer matrix provides improvedreactive organic compound properties and a reduced tendency to releasepolymer residue (e.g. acetaldehyde).

Polymeric Materials

In general, thermoplastic resins may be used with the additivecompositions of the invention, wherein the compatibility of thecyclodextrin and carbon with the polymer matrix is the limiting factor.Non-limiting examples of useful thermoplastics include polyamides,polycarbonates, polyurethanes, polyethers, polyketones, polystyrene,polyacrylates, polyphenylene oxide, poly(vinyl chloride), or copolymersor blends thereof. More preferably, the thermoplastic polymer is apolyolefin or a polyester.

Polyolefins that are industrially useful include polyethylene,polypropylene, and copolymers thereof with various monomers includingother olefins such as 1-butene, 1-hexene, 1-octene, and the like, orcopolymers with other useful monomers such as vinyl acetate, vinylchloride, vinylidene fluoride, acrylates, methacrylates, and the like.Any vinyl functional monomer can be copolymerized with ethylene orpropylene to provide a useful olefin copolymer.

Suitable polyesters are produced from the reaction of a diacid ordiester component comprising at least 60 mole percent terephthalic acid(TA) or C₁-C₄ dialkyl terephthalate, preferably at least 75 molepercent, and more preferably at least 85 mole percent; and a diolcomponent comprising at least 60 mole percent ethylene glycol (EG),preferably at least 75 mole percent, and more preferably at least 85mole percent. It is also preferred that the diacid component be TA, orthe dialkyl terephthalate component be dimethyl terephthalate (DMT), andthe diol component is EG. The mole percentage for all thediacids/dialkyl terephthalate components total 100 mole percent, and themole percentage of all diol components total 100 mole percent.

Alternatively, suitable polyesters are produced from the reaction of adiacid or diester component comprising at least 60 mole percent2,6-naphthalene dicarboxylic acid (NDA) or C₁-C₄ dialkyl napthalate,preferably at least 75 mole percent, and more preferably at least 85mole percent; and a diol component comprising at least 60 mole percentethylene glycol (EG), preferably at least 75 mole percent, and morepreferably at least 85 mole percent.

Where the polyester components are modified by one or more diolcomponents other than EG, suitable diol components of the describedpolyester can be selected from 1,4-cyclohexanedimethanol;1,2-propanediol; 1,3-propanediol; 1,4-butanediol;2,2-dimethyl-1,3-propanediol; 1,6-hexanediol; 1,2-cyclohexanediol;1,4-cyclohexanediol; 1,2-cyclohexanedimethanol;1,3-cyclohexanedimethanol; and diols containing one or more oxygen atomsin the chain, for example diethylene glycol, triethylene glycol,dipropylene glycol, tripropylene glycol or mixtures of these and thelike. In general, these diols contain 2 to 18, and preferably 2 to 8carbon atoms. Cycloaliphatic diols can be employed in their cis or transconfiguration or as mixtures of both forms.

Where the polyester components are modified by one or more acidcomponents other than TA, suitable acid components of the linearpolyesters may be selected from the class of isophthalic acid;1,4-cyclohexanedicarboxylic acid; 1,3-cyclohexanedicarboxylic acid;succinic acid; glutaric acid; adipic acid; sebacic acid;1,12-dodecanedioic acid; 2,6-naphthalene dicarboxylic acid;2,7-naphthalene dicarboxylic acid, t-stilbene dicarboxylic acid,4,4′-bibenzoic acid, or mixtures of these or their anhydrideequivalents, and the like. In the case of polyethylene naphthalate,2,6-naphthalene dicarboxylic acid can be used in place of theterephthalic acid listed above.

A typical PET based polymer for the beverage container industry hasabout 97 mole percent PET and 3 mole percent isophthalate—thus it is thecopolymer polyethylene terephthalate/isophthalate. In the polymerpreparation, it is often preferred to use a functional acid derivativethereof such as dimethyl, diethyl or dipropyl ester of a dicarboxylicacid. The anhydrides or acid halides of these acids may also be employedwhere practical. These acid modifiers generally retard thecrystallization rate compare to terephthalic acid.

Conventional production of polyethylene terephthalate is well known inthe art and comprises reacting terephthalic acid (TA) (or dimethylterephthalate-DMT) with ethylene glycol (EG) at a temperature ofapproximately 200 to 250° C. forming monomer and water (monomer andmethanol, when using DMT). Because the reaction is reversible, the water(or methanol) is continuously removed, thereby driving the reaction tothe production of monomer. The monomer comprises primarily BHET(bishydroxyethylene terephthalate), some MHET (monohydroxyethyleneterephthalate), and other oligomeric products and small amounts ofunreacted raw materials. Subsequently, the BHET and MHET undergo apolycondensation reaction to form the polymer. During the reaction ofthe TA and EG it is not necessary to have a catalyst present. During thereaction of DMT and EG employing an ester interchange catalyst isrequired. Suitable ester interchange catalysts include compoundscontaining cobalt (Co), zinc (Zn), manganese (Mn), and magnesium (Mg),to name a few. Generally, during the polycondensation reaction thepreferred catalyst is antimony in the form of an antimony salt orcompound. Often bottle grade PET resin, during manufacture, is heatedunder inert ambient atmosphere to promote further polymerization in theresin or processed as an SSP resin. Typically bottle grade PET resin hasan intrinsic viscosity (IV) of about 0.70 to about 0.85 dL/g.

Cyclodextrin

The solutions and thermoplastic materials of the invention contain acyclodextrin compound that can comprise cyclodextrin or a cyclodextrinhaving one substituent group, preferably on a primary carbon atom. Suchcyclodextrin materials have been shown to be compatible withthermoplastic polyester materials in scavenging and barrier properties.The cyclodextrin material can be added to the thermoplastic and, duringmelt processing, provide scavenging properties and barrier properties inthe preform and in the final beverage container. The cyclodextrinmaterials, under good manufacturing conditions of time and temperature,are compatible, do not burn, and do not result in the formation of hazeor reduced structural properties or clarity in the appearance of thepolymer in the final container.

Cyclodextrin (CD) is a cyclic oligosaccharide consisting of at leastfive, preferably six, glucopyranose units joined by an α(1→4) linkage.Although cyclodextrin with up to twelve glucose residues are known, thethree most common homologs (α-cyclodextrin, β-cyclodextrin andγ-cyclodextrin) having 6, 7 and 8 residues are known and are useful inthe invention.

Cyclodextrin is produced by a highly selective enzymatic synthesis fromstarch or starch-like materials. They commonly consist of six, seven, oreight glucose monomers arranged in a donut shaped ring, which aredenoted α, β and γ cyclodextrin respectively (See FIG. 1). The specificcoupling of the glucose monomers gives the cyclodextrin a rigid,truncated conical molecular structure with a hollow interior of aspecific volume. This internal cavity, which is apolar (i.e., isattractive to a wide range of hydrocarbon materials when compared to thehydrophilic exterior, is a key structural feature of the cyclodextrin,providing the ability to complex molecules (e.g., aromatics, alcohols,halides and hydrogen halides, carboxylic acids and their esters, etc.).The complexed molecule must satisfy the size criterion of fitting atleast partially into the cyclodextrin internal cavity, resulting in aninclusion complex. These complexes are unusual in that only secondarybonding occurs between the CD and guest, yet their stability can bequite high depending on the characteristics of the cyclodextrin andguest. A metal-cyclodextrin assembly demonstrates all the basic bondingmodes (non-specific Van der Waals bonds, hydrogen bonds andligand-to-metal bonds) in a singular molecular system.

Properties of CD α-CD β-CD γ-CD Degree of 6 7 8 polymerization (n =)Molecular Size (Å) inside diameter 5.7 7.8 9.5 outside diameter 13.715.3 16.9 height 7.0 7.0 7.0 Specific Rotation [α]²⁵ _(D) +150.5 +162.5+177.4 Color of iodine Blue Yellow Yellow- complex Brown Solubility inwater (g/100 ml) 25° Distilled water 14.50 1.85 23.20The oligosaccharide ring forms a torus, as a truncated cone, withprimary hydroxyl groups of each glucose residue lying on a narrow end ofthe torus. The secondary glucopyranose hydroxyl groups are located onthe wide end. The torus interior is hydrophobic due to the presence ofmethylene (—CH₂—) and ether (—O—) groups. The parent cyclodextrinmolecule, and useful derivatives, can be represented by the followingformula (the ring carbons show conventional numbering) in which thevacant bonds represent the balance of the cyclic molecule:

wherein n=6, 7 or 8 glucose moieties and R₁ and R₂ are primary orsecondary hydroxyl or substituent groups (methoxy, acetyl, etc.),respectively. The cyclodextrin molecule shown above has —OH groupsavailable for reaction at the 6-position (a primary group) and at the 3-and 2-positions (secondary groups). While the preferred cyclodextrincompound for use in aldehyde scavenging is a β-cyclodextrin, substitutedcyclodextrins can be used to enhance barrier properties. The preferredcyclodextrin is substituted at one or more of the R₁ primary hydroxylsin the oligomer. Preferred cyclodextrins are first β-CD, then α-CD andare primarily substituted at the 6-position.

The preferred preparatory scheme for producing a derivatizedcyclodextrin material having a functional group compatible with thethermoplastic polymer involves reactions at the primary hydroxyls with aminimum of the secondary hydroxyls of the cyclodextrin molecule beingsubstituted. Coordination compounds or metal complexes in which themodified cyclodextrin acts as a ligand requires the secondary hydroxylgroups to be free of a derivative. A sufficient number of primaryhydroxyls need to be modified to possess compatibility with the polymerand thermal stability in the process. Generally, we have found that abroad range of pendant substituent moieties can be used on the molecule.These derivatized cyclodextrin molecules can include acylatedcyclodextrin, alkylated cyclodextrin, cyclodextrin esters such astosylates, mesylate and other related sulfo derivatives,hydrocarbyl-amino cyclodextrin, alkyl phosphono and alkyl phosphatocyclodextrin, imidazoyl substituted cyclodextrin, pyridine substitutedcyclodextrin, hydrocarbyl sulfur containing functional groupcyclodextrin, silicon-containing functional group substitutedcyclodextrin, carbonate and carbonate substituted cyclodextrin,carboxylic acid and related substituted cyclodextrin and others. Thesubstituent moiety must include a region that provides compatibility tothe derivatized material.

Acyl groups that can be used as compatibilizing functional groupsinclude acetyl, propionyl, butyryl, trifluoroacetyl, benzoyl, acryloyland other well-known groups. The formation of such groups on either theprimary or secondary ring hydroxyls of the cyclodextrin molecule involvewell-known reactions. The acylation reaction can be conducted using theappropriate acid anhydride, acid chloride, and well-known syntheticprotocols. Peracylated cyclodextrin can be made. Further, cyclodextrinhaving less than all of available hydroxyls substituted with such groupscan be made with one or more of the balance of the available hydroxylssubstituted with other functional groups.

Cyclodextrin materials can also be reacted with alkylating agents toproduced an alkylated cyclodextrin, a cyclodextrin ether. Alkylatinggroups can be used to produce peralkylated cyclodextrin using sufficientreaction conditions to exhaustively react the available hydroxyl groupswith the alkylating agent. Further, depending on the alkylating agent,the cyclodextrin molecule used in the reaction conditions can producecyclodextrin substituted at less than all of the available hydroxyls.Typical examples of alkyl groups useful in forming the alkylatedcyclodextrin include methyl, propyl, benzyl, isopropyl, tertiary butyl,allyl, trityl, alkyl-benzyl and other common alkyl groups. Such alkylgroups can be made using conventional preparatory methods, such asreacting the hydroxyl group under appropriate conditions with an alkylhalide, or with an alkylating alkyl sulfate reactant. The preferredcyclodextrin is a simple lower alkyl ether, such as methyl, ethyl,n-propyl, t-butyl, etc. and is not peralkylated but has a degree ofsubstitution of about 0.3 to 1.8.

Tosyl(4-methylbenzene sulfonyl) mesyl (methane sulfonyl) or otherrelated alkyl or aryl sulfonyl forming reagents can be used inmanufacturing compatibilized cyclodextrin molecules for use inthermoplastic resins. The primary —OH groups of the cyclodextrinmolecules are more readily reacted than the secondary groups. However,the molecule can be substituted on virtually any position to form usefulcompositions.

Such sulfonyl containing functional groups can be used to derivatizeeither of the secondary hydroxyl groups or the primary hydroxyl group ofany of the glucose moieties in the cyclodextrin molecule. The reactionscan be conducted using a sulfonyl chloride reactant that can effectivelyreact with either primary or secondary hydroxyls. The sulfonyl chlorideis used at appropriate mole ratios depending on the number of targethydroxyl groups in the molecule requiring substitution. Eithersymmetrical (per substituted compounds with a single sulfonyl moiety) orunsymmetrical (the primary and secondary hydroxyls substituted with amixture of groups including sulfonyl derivatives) can be prepared usingknown reaction conditions. Sulfonyl groups can be combined with acyl oralkyl groups generically as selected by the experimenter. Lastly,monosubstituted cyclodextrin can be made wherein a single glucose moietyin the ring contains between one and three sulfonyl substituents. Thebalance of the cyclodextrin molecule remains unreacted.

Amino and other azido derivatives of cyclodextrin having pendentthermoplastic polymer containing moieties can be used in the sheet, filmor container of the invention. The sulfonyl derivatized cyclodextrinmolecule can be used to generate the amino derivative from the sulfonylgroup substituted cyclodextrin molecule via nucleophilic displacement ofthe sulfonate group by an azide (N₃ ⁻¹) ion. The azido derivatives aresubsequently converted into substituted amino compounds by reduction.Large numbers of these azido or amino cyclodextrin derivatives have beenmanufactured. Such derivatives can be manufactured in symmetricalsubstituted amine groups (those derivatives with two or more amino orazido groups symmetrically disposed on the cyclodextrin skeleton or as asymmetrically substituted amine or azide derivatized cyclodextrinmolecule. Due to the nucleophilic displacement reaction that producesthe nitrogen containing groups, the primary hydroxyl group at the6-carbon atom is the most likely site for introduction of anitrogen-containing group. Examples of nitrogen containing groups thatcan be useful in the invention include acetylamino groups (—NHAc),alkylamino including methylamino, ethylamino, butylamino, isobutylamino,isopropylamino, hexylamino, and other alkylamino substituents. The aminoor alkylamino substituents can be further reacted with other compoundsthat react with the nitrogen atom to further derivatize the amine group.Other possible nitrogen containing substituents include dialkylaminosuch as dimethylamino, diethylamino, piperidino, piperizino, quaternarysubstituted alkyl or aryl ammonium chloride substituents. Halogenderivatives of cyclodextrins can be manufactured as a feed stock for themanufacture of a cyclodextrin molecule substituted with acompatibilizing derivative. In such compounds, the primary or secondaryhydroxyl groups are substituted with a halogen group such as fluoro,chloro, bromo, iodo or other substituents. The most likely position forhalogen substitution is the primary hydroxyl at the 6-position.

Hydrocarbyl substituted phosphono or hydrocarbyl substituted phosphatogroups can be used to introduce compatible derivatives onto thecyclodextrin. At the primary hydroxyl, the cyclodextrin molecule can besubstituted with alkyl phosphato, aryl phosphato groups. The 2, and 3,secondary hydroxyls can be branched using an alkyl phosphato group.

The cyclodextrin molecule can be substituted with heterocyclic nucleiincluding pendent imidazole groups, histidine, imidazole groups,pyridino and substituted pyridino groups.

Cyclodextrin derivatives can be modified with sulfur containingfunctional groups to introduce compatibilizing substituents onto thecyclodextrin. Apart from the sulfonyl acylating groups found above,sulfur containing groups manufactured based on sulflhydryl chemistry canbe used to derivatize cyclodextrin. Such sulfur containing groupsinclude methylthio (—SMe), propylthio (—SPr), t-butylthio (—S—C(CH₃)₃),hydroxyethylthio (—S—CH₂CH₂OH), imidazolylmethylthio, phenylthio,substituted phenylthio, aminoalkylthio and others. Based on the ether orthioether chemistry set forth above, cyclodextrin having substituentsending with a hydroxyl aldehyde ketone or carboxylic acid functionalitycan be prepared. Such groups include hydroxyethyl, 3-hydroxypropyl,methyloxylethyl and corresponding oxeme isomers, formyl methyl and itsoxeme isomers, carbylmethoxy (—O—CH₂—CO₂H) and carbylmethoxymethyl ester(—O—CH₂CO₂—CH₃).

Cyclodextrin derivatives with compatibilizing functional groupscontaining silicone can be prepared. Silicone groups generally refer togroups with a single substituted silicon atom or a repeatingsilicone-oxygen backbone with substituent groups. Typically, asignificant proportion of silicone atoms in the silicone substituentbear hydrocarbyl (alkyl or aryl) substituents. Silicone substitutedmaterials generally have increased thermal and oxidative stability andchemical inertness. Further, the silicone groups increase resistance toweathering, add dielectric strength and improve surface tension. Themolecular structure of the silicone group can be varied because thesilicone group can have a single silicon atom or two to twenty siliconatoms in the silicone moiety, can be linear or branched, have a largenumber of repeating silicone-oxygen groups, and can be furthersubstituted with a variety of functional groups. For the purposes ofthis invention, the simple silicone containing substituent moieties arepreferred including trimethylsilyl, mixed methyl-phenyl silyl groups,etc. We are aware that certain β-CD and acetylated and hydroxy alkylderivatives are available commercially.

Preferably, the cyclodextrin compound utilized in the technology of theinvention involves a modified or substituted β- or α-cyclodextrin.Preferred cyclodextrin materials are substituted substantially on the6-OH of the glucose moiety in the cyclodextrin ring. The free hydroxylgroups at the 3- and 2-position of the glucose moieties in thecyclodextrin ring are important for metallic catalyst complex formation.The degree of substitution (D.S.) of the cyclodextrin material can rangefrom about 0.3 to 2.5 or 0.3 to 2; preferably the degree of substitutioncan range from about 0.5 to 1.8. Further the degree of substitution hasan important role in ensuring that the cyclodextrin is compatible withthe polymer melt, but is not so substituted that the cyclodextrin cannotparticipate in complexing catalyst residues. We have further found thatthe amount of substituted cyclodextrin material useful in preventing theformation of aldehyde by complexing metallic catalyst residues is lessthan the amount of cyclodextrin typically used in barrier structures forvolatile organic compounds. The effective amount of a substitutedcyclodextrin for aldehyde suppression ranges from about 100 ppm to 1400ppm based on the polymer composition as a whole, preferably 350 ppm to900 ppm. We believe the mechanistic action of the substitutedcyclodextrin material is one or more of the secondary hydroxyl groupsform a coordination complex with the catalyst residues to form ametallocyclodextrin where more than one metal ion is bound percyclodextrin. While the amounts of cyclodextrin useful in preventingformation of organic residuals during preform and bottle manufacture areless and that used in barrier applications, even at reduced amounts, thecyclodextrin materials can provide a degree of barrier properties.According to the concentrations disclosed in this application,regenerated acetaldehyde formation is substantially reduced in thepolyester and some degree of barrier property is achieved. To achievethese results, a substantial and effective fraction of the cyclodextrinmust be available for catalyst residue complexation to accomplish thegoal of the invention. The compatible cyclodextrin compounds areintroduced into the melt thermoplastic substantially free of aninclusion complex or inclusion compound.

Cyclodextrin Bonded to a Polymer

Grafting cyclodextrin to a polymer backbone to form pendant cyclodextringroups is known in the art. Wood, et al., U.S. Pat. No. 7,166,671,previously incorporated by reference in its entirety, disclose agrafting reaction wherein cyclodextrin is reacted with e.g. maleicanhydride groups present along a polyolefin backbone. Cyclodextrinsuseful in the grafting reaction can be unsubstituted or can have one ormore substituent groups, such as O-methyl or O-acetyl. Grafting istypically carried out using any of thermal processing techniques knownto the skilled artisan. For example, a Plastograph® mixer, availablefrom the Brabender® GmbH and Co. KG of Duisburg, West Germany, may beused to melt a polymer and incorporate cyclodextrin and carbon. In mostcases an extruder will be used to blend a polymer and cyclodextrin withcarbon to form a grafted cyclodextrin. Twin screw or single screwextrusion may be used.

Twin screw Parameters Value Rate (lbs./hr.) 30 RPM 400 Torque 38Reaction Zone Temp. (° C.) 25 Die Melt Temp. (° C.) 207 CD Moisture 0.5Resonce, First (sec) 30 Cleared out (sec) 90 SME (kj/kg) 873

Extruders used to blend the additive compositions can be, for example, asingle screw extruder, such as a single screw extruder available fromthe Davis-Standard Co. of Pawcatuck, N.J. Alternatively, a custom singlescrew extruder and/or custom screws for a single screw extruder may beemployed. Such equipment is available from The Madison Group, Madison,Wis. In some processes, a co- and counter rotating twin screw extrudermay be used to extrude compositions of the inventions. Such equipment isavailable from e.g. Coperion (Krupp Warner Pfleiderer). of Ramsey, N.J.,American Leistritz Extruder Corp, of Somerville, N.J., Berstorff Corp.,of Florence, Ky., Haake Thermo Fisher Scientific, of Waltham, Mass. andCW Brabender Instruments, of S. Hackensack, N.J.

An alternative to grafting is to incorporate cyclodextrin integrallyinto a polymer backbone by employing cyclodextrin as a monomer in apolymerization reaction, specifically the hydroxyl groups oncyclodextrin as reactive moieties in a polymerization reaction. Usinghydroxyl groups, addition polymers such as polyesters and polyurethanesare easily made. For example, U.S. Patent Publication No. 2004/0110901,JP 59227906, JP 05051402, WO 93/05084, U.S. Pat. No. 4,547,572, U.S.Pat. No. 4,274,985, and EP 0454910A1, previously incorporated herein byreference, describe various methods of incorporating cyclodextrin into apolymer. Additionally, U.S. Pat. No. 6,613,703, also previouslyincorporated by reference, discloses a method of attaching cyclodextrinto a polymer via electron beam.

Activated Carbon

Activated carbons (CAS No. 7440-44-0) are porous synthetic solidmaterials that are commonly used in a wide variety of applications forpurification, decolorization, and odor removal of gases and liquids.Activated carbons are used generally in particulate form and availablein powder and granular forms. They are characterized by an open, porousstructure that provides a large surface area, which in turn facilitatesadsorption of a variety of chemicals. The ability of the activatedcarbon to scavenge compounds is directly related to the inner surfacearea of the particles.

In commercially available activated carbons (typically called charcoal),the inner surface area is typically 500-1500 m²/g as measured byemploying the method of Brunauer, Emmett, and Teller's (BET) nitrogenadsorption isotherm. (S. Brunauer, P. H. Emmett and E. Teller, J. Am.Chem. Soc., 1938, 60, 309.) Total surface area and pore volume/structureare critical parameters when specific uses of activated carbon arecontemplated. Pore volume limits the size of molecules that can beabsorbed, while the total surface area dictates the total amount ofmaterials that may be absorbed.

Pore sizes in activated carbons are categorized as micropores, which areup to 2 nm, mesopores, which are between 2 and 50 nm, and macropores,which are greater than 50 nm. The role of macropores is principally thatof a passage into the interior of the carbon particle; these pores donot contribute greatly to the overall surface area of the particle oreffectively entrap molecules. Micropores are principally the place whereadsorption of chemicals takes place.

The original source of the carbon, as well as the means to activate thecarbon, determines the pore size distribution. In theory, any substancecontaining carbon may be used as a starting material. Materials areactivated either by chemical or gas activation at temperatures between400° C.-1000° C. Wood, sawdust, and peat are most often treated bychemical activation. Gas activation most often employs an initialcarbonizing (i.e. burning) step. Thus, wood charcoal, nut shellcharcoal, bituminous coals, and coke from brown coal or peat are typicalmaterials used for gas activation. Gas activation of coconut shellcharcoal provides a high proportion of micropores; gas activation ofsoft wood charcoal provides a greater proportion of macropores. Chemicalactivation is considered the most useful in general to provide for largeproportions of both micropores and mesopores. Combinations of gas andchemical activation are also used.

Chemical activation, most typically accomplished with zinc chloride andphosphoric acid, relies on dehydrating action of these chemicals onstarting materials that commonly include non-carbonized (unburned) peator sawdust. After contacting the chemical to the carbonaceous startingmaterial, temperatures of 400° C.-1000° C. cause the opening up ofpores. After heating the chemicals are removed by extraction to providethe finished product having the same macroscopic form as the startingmaterial.

Gas activation most typically employs gases containing oxygen. Thus,steam or carbon dioxide are contacted with the starting material attemperatures of 800° C.-1000° C. to result in a partially decomposedparticle wherein the absence of the decomposed materials form the pores.

Activated carbon has several important uses including solutionpurification of organic compounds; removal of tastes and odors fromdomestic and industrial water supplies, wastewater, vegetable and animalfats and oils, alcoholic beverages, chemicals, and pharmaceuticals;waste water treatment; purification of gases; liquid phase recovery;separation processes; and as a support for catalysts. Many organiccompounds such as chlorinated solvents, non-chlorinated solvents,gasoline, pesticides and trihalomethanes can be adsorbed by activatedcarbon. It is also effective for removal of chlorine gas and moderatelyeffective for removal of some heavy metals.

Particularly preferable in certain applications is acid-washed carbon.Removal of deleterious organic compounds is more effective at pH of lessthan 7. See DeSilva, F. J., “The Issue of pH Adjustment in Acid-WashedCarbons”, Water Conditioning and Purification, May 2001, pp. 40-44. Acarbon that causes pH to rise above 7 at the outset may not be effectiveat removal of organics until several rinses in water result in a lowerpH. Any activated carbon that is not acid-washed usually produces aninitial effluent in water having a pH of greater than 7. The actualinitial pH depends on several factors, including ash content in thestarting material. Initial pH can be as high as 10.5 when the carbon isimmersed in water. Washing the carbon in acid creates a lower initial pHafter rinsing the acidifying agent from the carbon, providing forimproved uptake of organic VOC and other deleterious compounds.

Purification of Cyclodextrin and Entraining Activated Carbon Particles

We have found that, purifying the cyclodextrin compounds describedabove, cyclodextrin impurities can be effectively removing usingpurification techniques including contacting the aqueous cyclodextrinsolution with activated charcoal or activated carbon absorbent. We foundthat using these techniques reduced the concentration of impurities inthe aqueous cyclodextrin solutions to levels that do not contribute tocolor generation in the polyester material, form undesirable organicmaterials or reduce antimony.

Cyclodextrin may also be purified using nanofiltration techniques. Innanofiltration or reverse osmosis processing, the aqueous cyclodextrinmaterial is directed into the appropriate purification equipment and ismaintained, at an appropriate pressure, for appropriate period of timeto ensure that a substantial proportion of the impurity in thecyclodextrin material passes through the filter or reverse osmosismembrane while the cyclodextrin material is retained in the rejectaqueous solution. In this regard, about 700 to 1,200 liters of solutionare passed through the equipment per square meter of filter or membraneand a rate of about 125 to 2,000 liters of solution per hour. Theeffluent passing through the filter or membrane comprises about 60 to98% of the input stream. Typically, the nanofiltration or reverseosmosis equipment is operated at an internal pressure of about 125 to600 psi.

Decolorizing resins like Dowex SD-2 (a tertiary amine functionalizedmacroporous styrene divinylbenzene copolymer) are used to remove PETyellow-color causing materials from aqueous cyclodextrin solutions.Other resins like Dowex Monosphere 77 (a weak base anion resin), DowexMAC-3 (a weak cation resin), and Dowex 88 (a strong acid cation) canalso be used in combination (infront) with Dowex SD-2. These resins canbe operated with flow of 2 to 25 liters per minute per ft² of resin.

The purified cyclodextrin may also be purified by simply addingactivated carbon to the cyclodextrin in a solvent, and filtering off thecarbon after a suitable period to allow for the carbon to adsorbimpurities. We have further found that, in certain ranges ofcyclodextrin concentration, an amount of the activated carbon adsorbentremains in the cyclodextrin solution after the bulk activated carbonfrom the purification process is filtered away from the solution. Insuch a purification processes, the aqueous cyclodextrin solution isprepared at concentration of about 1.5 to about 50 wt. percent of thecyclodextrin compound in the aqueous solution. Such an aqueous solutionis then contacted with the carbon absorbent at about 10 to 350 literssolutions per kilogram of absorbent. The residence time of the solutionin contact with the absorbent can be adjusted to obtain substantialimpurities removal. The solution, however, is generally maintained incontact with the absorbent for a time period of about 0.5 to 24 hours.

After the contact period, the solution is filtered using filters havingpore sizes from about 0.1 to about 20 μm. Microfiltration used to removeparticles on the order of 10 micron or less in size. The objective ofthe filtration step of the process is the removal of particulate matterand/or undissolved solids having a size of from about 0.1 to 1.0microns, preferably from about 0.2 to 5 microns, from the liquid.Examples of suitable membrane types include ceramic, porous carbon, andpolymeric. Suitable membranes and membrane filtration apparatus areavailable from TAMI, Pall, WACO, Filtros Techsep, Ceramem, Koch and GEOsmonics. The filtration preferably takes place at a temperature ofabout 50-80° C.

Additionally, an amount of carbon can simply be added to purifiedcyclodextrin after any of the purifying steps outlined above. Thismethod allows for the maximum levels of uncomplexed carbon pores, whichin turn results in the most available carbon pore space for impurityscavenging in the end applications of the invention.

The following is a method for evaluating dried additive compositions forthermal stability based upon the potential of generating off-color. Thismethod mimics the processing of injection molding cyclodextrin coatedPET chip. Approximately 1.5 mL (approx. 1.7 g) of a 35 wt.-%cyclodextrin solution having entrained activated carbon particles at 0.2wt % is placed into a 20 mL headspace vial (or equivalent).

Water is evaporated from the solution by heating the vial using alaboratory hot plate (or equivalent) at a moderate temperature. The vialis periodically agitated during heating, and the interior of the vial isswabbed with a lint free wipe to remove condensate. When the residuebecomes viscous and begins to bubble the vial is removed from the heatand gently rolled to coat the interior walls of the vial evenly. Thecoated vial is placed into an oven at 60° C. for approximately 10minutes to completely solidify the residue by removing all remainingwater. The clear residue may bubble and haze slightly when evaporationis complete. The vial is removed when dry and placed into a 280° C. ovenfor exactly 2 minutes. If oven temperature drops when placing the vialinto the oven, begin timing only when the oven temperature is >270° C.The vial is removed and allowed to cool to room temperature. The heattreated residue is dissolved in 5 mL of deionized water, the liquid istransferred to a syringe and filtered through a 0.22 μm syringe filter.The filtrated is analyzed by a visible wavelength spectrophotometer at570 nm. Acceptable residue should remain colorless to just slightly offyellow.

The above purification, solution, and filtration techniques apply tounsubstituted or substituted α-, β, or γ-cyclodextrin. Afterpurification of cyclodextrin, the cyclodextrin may be grafted to apolymer to form one embodiment of the additive compositions of theinvention. Carbon is typically added after, or contemporaneously with,the grafting reaction.

Masterbatches of Additive Compositions and Polymer

The cyclodextrin compound can be incorporated onto the chip or pellet bycoating the chip or pellet or similar structure with a liquid coatingcomposition containing an effective amount of the cyclodextrin,substituted cyclodextrin, or polymer reacted cyclodextrin, plusactivated carbon. Such coating compositions are typically formed using aliquid medium. Liquid media can include aqueous media or organic solventmedia. Aqueous media are typically formed by combining water withadditives or other components to form coatable aqueous dispersions orsolutions. Solvent based dispersions are based on organic solvents andcan be made using known corresponding solvent based coating technology.The liquid coating compositions of the invention can be contacted with athermoplastic pellet (also called “chip” or “flake”) using any commoncoating technology including flood coating, spray coating, fluidized bedcoating, electrostatic coating or any other coating process that canload the pellet with sufficient cyclodextrin and carbon to act as ascavenger or barrier material in the final article when the masterbatchis blended with untreated polymer pellets. Careful control of the amountand thickness of the ultimate coating optimizes the scavenger andbarrier properties without waste of material, maintains clarity andcolor in the thermoplastic bottle and optimizes polyester physicalproperties. The coatings are commonly applied to the pellet and theliquid carrier portion of the solution or dispersion is removedtypically by heating leaving a dry coating on the pellet. When dry,substantially no solution or liquid medium is left on the pellet.Commonly, the coated pellets are dried in a desiccant-dryer to removetrace amounts of residual solvent before thermal processing. Typically,pellets are dried to 50 ppm or less of solvent.

Alternatively, masterbatch compositions of the invention may be formedby extrusion blending thermoplastic polymer with cyclodextrin,substituted cyclodextrin, or polymer bonded cyclodextrin and carbonparticles. This method typically employs the additive blend in the formof a powder. The powder is typically an admixture of cyclodextrin orsubstituted cyclodextrin and carbon, though it may be dried afterfiltration or centrifugation of a solution of the additive as describedabove. The powder is metered into an extruder so as to contact thethermoplastic resin that is in a molten state. The extrusion may be asimple blending process, or it may be a means to induce grafting ofcyclodextrin or substituted cyclodextrin onto the polymer backbone. Suchgrafting reactions are described in U.S. Pat. No. 7,166,671, previouslyincorporated by reference in its entirety.

After extrusion blending, the masterbatch composition is pelletized forconvenient storage. Pelletizing typically involves extruding themasterbatch in the form of a strand, passing the strand through atemperature controlled water bath to cool the strand, passing the strandthrough a strand cutter to form the pellet, and drying the water fromthe pellet prior to storing.

Articles Containing the Additive Compositions

Articles of the present invention may be made by any technique commonlyemployed in the art to blend thermoplastic materials and shape them intoa final form. Most advantageously, articles of the invention can beformed by extrusion blending thermoplastic polymer with cyclodextrin,substituted cyclodextrin, or polymer bonded cyclodextrin and carbonparticles, followed by a thermal forming process.

Extrusion blending typically employs the additive blend in the form of apowder. The powder is typically an admixture of cyclodextrin orsubstituted cyclodextrin and carbon, though it may be dried afterfiltration or centrifugation of a solution of the additive as describedabove. The powder is metered into an extruder so as to contact thethermoplastic resin that is in a molten state. The extrusion may be asimple blending process, or it may be a means to induce grafting ofcyclodextrin or substituted cyclodextrin onto the polymer backbone. Suchgrafting reactions are described in U.S. Pat. No. 7,166,671, previouslyincorporated by reference in its entirety.

Extrusion blending may also be used to blend masterbatch pellets withuntreated thermoplastic pellets. The masterbatch pellets may be surfacecoated or extrusion blended, as is described above. The two types ofpellets are metered into an extruder to provide the desired endconcentration of cyclodextrin groups and carbon particles in thefinished article.

After extrusion blending, a final article is formed from the moltenblend of thermoplastic resin, cyclodextrin, and carbon particles.Commonly employed techniques of forming a final article includeextrusion, coextrusion, profile extrusion, injection molding, blowmolding, injection blow molding, electrospinning; spunbonding,meltblowing, uniaxial or biaxial orientation, or combinations thereof.Additionally, specialized techniques may be employed to provide certainarticles, wherein one or more components of the article comprisecyclodextrin and activated carbon. For example, a bicomponent fiber maybe made using a polyolefin having grafted cyclodextrin and carbonparticles as one component and a second resin, such as polyester, assecond component. Bicomponent fibers and methods of making them aredisclosed in Krueger et al., U.S. Pat. No. 4,795,668, which isincorporated herein in its entirety.

In another example of a specialized technique used to make a finalarticle of the invention, injection blow molding processes are used toproduce polyester bottles. Two manufacturing techniques are typicallyused. In one method, a preform is made by injection molding techniquesin a preform shape having the neck and screw-cap portion of the bottlein approximately useful size but having the body of the preform in aclosed tubular form substantially smaller than the final bottle shape. Asingle component or multi-layered perform can be used. The preform isthen inserted into a blow-molding machine where it is heated enough toallow the preform to be inflated and blown into the appropriate shape.Alternatively, the resin can be injection blow molded over a steel-corerod. The neck of the bottle is formed with the proper shaped receivedclosures (cap) and resin is provided around the temperature-conditionedrod for the blowing step. The rod with the resin is indexed into themold and the resin is blown away from the rod against the mold walls.The resin cools while in contact with the mold forming the transparentbottle. The finished bottle is ejected and the rod is moved again in theinjection molding station. This process is favored for singlecylindrical bottles.

The most common machine involves a four station apparatus that caninject resin, blow the resin into the appropriate shape, strip theformed container from the rod and recondition the core rod prior to therepeat of the process. Such containers are typically manufactured withthe closure fitment portion comprising a threaded neck adapted to ametal screw cap. The bottle bottom typically has a lobed design such asa four-lobe or five-lobe design to permit the bottle to be placed in astable upright position. The manufacturing equipment has beencontinually upgraded to add blowing stations and increased throughput.

Raw material used in any of the thermoforming procedures is a chip formor a pelletized thermoplastic polyester. The thermoplastic polyester ismade in the form of a melt and is converted to bulk polymer. The meltcan be easily reduced to a useful pellet or other small diameter chip,flake or particulate. The pellet, chip, flake or particulate polyestercan then be blended with the derivatized cyclodextrin material untiluniform, dried to remove moisture, and then melt extruded underconditions that obtain a uniform dispersion or solution of the modifiedor derivatized cyclodextrin and polyester material. The resultingpolyester pellet is typically substantially clear, uniform and ofconventional dimensions. The pellet preferably contains about 0.01 toabout 0.14 wt-% of the cyclodextrin compound, more preferably about0.035 to about 0.09 wt-% of the cyclodextrin compound, polyester pelletcontaining the modified cyclodextrin material can then be incorporatedinto the conventional preform or parison with injection moldingtechniques. The products of these techniques contain similar proportionsof materials.

Care must be taken during the manufacture of the preform or parison andthe final manufacture of the container. During the manufacture of theperform and later during the manufacture of the container, sufficientheat history in terms of maintaining the melt polymer at a settemperature for a sufficient amount of time to obtain adequatescavenging and to thoroughly disperse the cyclodextrin material in thepolymer matrix must be achieved. However, the time and temperature ofthe steps should not be so long as the cyclodextrin material canthermally decompose (i.e., ring open the cyclodextrin) resulting in aloss of scavenging capacity and barrier properties accompanied bypolymer yellowing. Polymer haze can result during stretch blow moldingunless a cyclodextrin derivative with a melting point below the preformreheat temperature is selected. Cyclodextrins with melting pointsgreater than the preform reheat temperature will produce microvoids inthe biaxially oriented bottle wall giving a hazy appearance to thepolymer. Accordingly, depending on the equipment involved, thethermoplastic polyester is maintained in a melt form at a temperaturegreater than about 260° C., preferably about 270° C. to 290° C. for atotal residence time greater than about 90 seconds preferably about120±30 seconds to ensure adequate metal residue complexation duringinjection molding while ensuring that the cyclodextrin material preventsacetaldehyde generation. The total residence time is determined from thecycle time of the injection molding machine.

Turning to FIG. 2, the container generally shown at 20 comprises a body22, a base 24 and a cap portion 26. The overall shape of the containeris formed in a thermoplastic blow molding operation. Base 24 is aself-supporting base formed during bottle manufacture. Such a bottle cancontain either a second layer 17, prepared from a parison having asecond thermoplastic material formed during parison formation or canhave a second layer 17 derived from a liquid coating material. Theliquid coating material can be either a parison coating or a bottlecoating.

Other preferred embodiments of the present invention are absorbentarticles, wherein one or more films, sheets, or nonwoven layers arepresent and can advantageously incorporate the compositions of theinvention. Thermoplastic polyolefins are known to be used as componentsof absorbent articles. Where they are employed, cyclodextrin and carbonof the disclosure can be incorporated to scavenge undesirableodor-causing chemicals. By an effective amount it is meant, for example,that at least 10% of trained odor-sensing test subjects will notice areduction in the odor emanating from the absorbent article or componentof the absorbent article, or at least 30%, or at least 50%, or even atleast 70% of the trained test subjects when compared to an article freeof a cyclodextrin and carbon composition.

In some embodiments, a cloth-like or reinforcing backsheet layer can begenerally made up, for example, of polypropylene spunbond nonwovenproduced in a manner known to those skilled in the art. By replacing aportion of the normal polypropylene polymer used in the spunbond processwith an effective amount of the polypropylene grafted cyclodextrin andcarbon of the disclosure, effective reduction of odors emanating fromthe absorbent article can be achieved. Alternatively, instead ofpolypropylene, the nonwoven can comprise copolymers of ethylene andα-octene, methyl acrylate, or ethyl acrylate. The nonwoven mayincorporate grafted cyclodextrin, substituted cyclodextrin, orunsubstituted cyclodextrin along with activated carbon. Any fiber,filament, or fabric containing thermoplastic polyolefins used for thispurpose can have incorporated therein cyclodextrin and activated carbonof the disclosure.

For example, FIG. 3 shows a food absorbent pad 30 having spunbond orporous top film 31 and spunbond or porous bottom film 33 and meltblownor absorbent core 32. Such an absorbent article may be used in the meatpacking industry by placing the pad underneath uncooked meat in a sealedpackage. Film 31, film 33 or core 32 may comprise a composition of theinvention, for example a blend of substituted cyclodextrin and activatedcarbon, to improve the scavenging of malodorous compounds by theabsorbent article.

Another useful embodiment of the present invention is a fuel tankwherein a cyclodextrin and carbon composition of the present inventionmay be incorporated. The five-layer coextruded fuel tank is the de factoindustry standard in North America. Coextruded tanks are designed tomeet strict evaporative fuel standards and consist of an inner layer ofHDPE joined by a tie layer and barrier layer of polyimide (nylon) orethylene-vinyl alcohol (EVOH) copolymer. The tie layer is an adhesiveresin formed by the copolymerization or graft polymerization of HDPEwith maleic acid, and has a functional group which adheres to apolyethylene chain polymer. An additional tie layer can be joined by alayer of “regrind” and an outer layer of HDPE. The use of the “regrind”layer adds an additional layer for a six-layer tank wall. In oneembodiment of the invention, the polymers and articles of the disclosurecan be used to substantially improve the barrier properties ofcommercial thermoplastic fuel tanks by adding activated carbon to afunctionalized HDPE resin grafted with cyclodextrin as the inner oroptionally the outer HDPE layer composition of the fuel tank to, forexample, reduce gasoline vapor permeation.

Thus, in embodiments the present disclosure provides an organic liquidand vapor impermeable vessel comprising a rigid structure having layersin the following order:

an outer polymer layer, such as an HDPE layer;

a barrier resin layer, such as Nylon or EVOH;

an adhesive resin layer; and

an inner polymer layer comprising a blend of a polyolefin and a modifiedpolyolefin and activated carbon, the modified polyolefin comprising acyclodextrin, the cyclodextrin being substantially free of a compound inits central pore, for example, an HDPE layer in admixture with activatedcarbon and a functionalized polymer resin grafted with cyclodextrin.

FIG. 4 shows a multilayered fuel tank construction 40 commonly used inthe industry. Schematic diagram of one embodiment of the multilayeredconstruction, 40A, shows outside HDPE layer 41, adhesive resin layer 42,barrier resin layer 43, another adhesive layer 42, and an inside HDPElayer 44. A second embodiment of the multilayered construction, 40B,shows outside HDPE layer 41, adhesive resin layer 42, barrier resinlayer 43, an inside HDPE layer 44. The barrier resin layer is mostcommonly ethylene-vinyl alcohol copolymer or nylon. In any of theselayers, a cyclodextrin and carbon composition of the invention may beincorporated. For example, one or both HDPE layers may be grafted withcyclodextrin and incorporate carbon. Alternatively, a barrier oradhesive layer can incorporate cyclodextrin, for example a substitutedcyclodextrin, and carbon particles. Inclusion of the compositions of theinvention are advantageous to prevent fuel fumes from breaching the tankand creating a flammability hazard.

We have also found the combination of cyclodextrin and activated carbonis important in achieving the goals of the invention. As discussedabove, the cyclodextrin material is applied to a pellet or chip in theform of an aqueous solution. Such solutions are made by dissolving orsuspending the cyclodextrin material in an aqueous medium. The aqueoussolution is prepared from cyclodextrin materials where the traceimpurities have been removed. These impurities can arise from theenzymatic manufacture of the cyclodextrin material producing linearstarches, saccharide and polysaccharide precursor materials or from thesynthetic reaction between the cyclodextrin material and reactants usedto form the derivatives. Materials that are present as impurities in thesubstituted cyclodextrin material that cause off-yellow color ininjection molded PET include iron, sodium chloride, acetic acid, ironacetate, sodium acetate, furfurals, linear starches and sugars,dehydrated linear starches, levoglucosan, levoglucosenone and proteins.

The foregoing discussion illustrates various embodiments of theapplication and the acetaldehyde reduction and the barrier andcomplexing properties of the materials of the invention. The followingexamples and data further exemplify the invention and contain a bestmode.

EXPERIMENTAL SECTION Example 1

A 35 wt.-% methyl beta cyclodextrin (degree of substitution 1.0,manufactured by Wacker-Chemie of Adrian, Mich.) solution was prepared indeionized water. Prior to preparing the solution, 0.10 wt % of coconutcharcoal previously ground in a mortar and pestle was blended into thedry cyclodextrin (16 hours @ 100° C.). The 35 wt % methyl betacyclodextrin solution containing activated carbon was centrifuged at 750rpm for 30 minutes. An upper aliquot of the centrifuged solution wasadded to a glass slide and then covered with a slip slide. Gray scale (8bit) digital images were then taken of the solution using a transmittedlight microscope (Olympus BH2, available from Olympus America Inc. ofMelville, N.Y.) with a 40× objective equipped with a 4 megapixeleyepiece camera. Six pictures were taken of the sample. A referencephotograph was taken of a stage micrometer for dimensional calibration.The images were analyzed by Optimas image analysis software (availablefrom the X Company of Y): a variable threshold was used, a binary filloperation was performed, and the data from each image was extracted. Theinformation extracted was the area equivalent diameter (AED). Theresults were obtained by analyzing the data using the statisticalpackage R.

FIG. 5 illustrates AED in microns and particle circularity in micronsfor the carbon particle distribution in 35 wt.-% methyl betacyclodextrin solution centrifuged at 750 rpm for 30 minutes. The areaequivalent diameter and the particle circularity were calculated fromthe area and perimeter of the image of the particle. The particlecircularity is the value obtained by dividing the square of theperimeter of a circle of equivalent area to the captured particle imageby 4π multiplied by the area of the captured particle image. Theparticle circularity is 1 when the captured particle image is a perfectcircle, and is less than 1 when the captured particle image is oblong orhas unevenness. For example, the particle circularity of an equilateralhexagon is 0.952, an equilateral pentagon is 0.930, that of anequilateral tetragon is 0.886, and an equilateral triangle is 0.777.

Example 2

Emery 3004 synthetic hydrocarbon oil manufactured by Cognis Corporation,Cincinnati, Ohio was infused with 0.20 wt % of coconut charcoalpreviously ground in a mortar and pestle. The oil with activated carbondispersion was centrifuged at 750 rpm for 30 minutes. An upper aliquotof the centrifuged oil was added to a glass slide and then covered witha slip slide. Gray scale (8 bit) digital images were then taken of theoil using an Olympus BH2 transmitted light microscope equipped with a40× objective and a 4 mega-pixel eyepiece camera. Two pictures weretaken of the sample. A reference photograph was taken of a stagemicrometer for dimensional calibration. The images were analyzed byOptimas image analysis software: a variable threshold was used, a binaryfill operation was performed, and the data from each image wasextracted. The information extracted was the area equivalent diameter(AED). The results were obtained by analyzing the data using thestatistical package R.

FIG. 6 is carbon particle distribution in Emery 3004 oil centrifuged at750 rpm for 30 minutes. The area equivalent diameter and the particlecircularity are calculated from the area and perimeter of the image ofthe particle.

Example 3

Dried β-cyclodextrin was analyzed for thermal stability based upon thepotential of generating volatile thermal decomposition products producedfrom impurities including acetic acid, formic acid, furfurals, linearstarches and sugars, dehydrated linear starches, levoglucosan,levoglucosenone and proteins. This method mimics the processing ofreactive extrusion where β-cyclodextrin is grafted onto maleic anhydridefunctionalized polyolefins, and any subsequent conversion of thematerial to form an article. β-Cyclodextrin (manufactured byWacker-Chemie of Adrian, Mich.) was prepared by dry blending 0.01, 0.10and 1.0 wt % of coconut charcoal previously ground in a mortar with drycyclodextrin (16 hours @ 100° C.). β-cyclodextrin, 0.5 grams was addedto a 40 mL headspace vial (available from IChem® Corp. of ) with aTeflon-faced septa screw cap. The vial with screw cap removed was heatedin an oven to 290° C. for exactly 2 minutes. The vial was removed fromthe oven and allowed to cool at room temperature for 40 seconds beforeapplying the Teflon-faced septa screw cap. Thermal decompositionproducts resulting from β-cyclodextrin impurities were measured in theheadspace inside the sealed vial by gas chromatography.

High-resolution gas chromatography (HRGC) operated with flame ionizationdetection (FID) was used to measure the headspace concentration ofvolatile thermal decomposition products. Volatile compounds in theheadspace were quantitatively collected by solid phase microextraction(SPME) from the test vial and analyzed by HRGC/FID. The 40-mL vial wasmaintained at 40° C. for 15 minutes prior to sampling the headspace. Theheadspace was sampled for 10 minutes using an 85 μm Carboxen/PDMSStableFlex® SPME fiber (Supleco, Inc. of Bellefonte, Pa.) and the SPMEfiber analyzed according to the GC method in Table 1.

TABLE 1 Gas chromatography conditions. HP 5890 GC Zone Temperatures:Setpoint Injector 250° C. Detector (FID) 330° C. Over Zone: Equib Time3.00 min. Oven Program: Initial Temp.:  75° C. Initial Time: 2.00 min.Level Rate (° C./min.) Final Temp. (° C.) Final Time (min) 1 10.0 1250.00 2 25.0 220 0.00 3 35.0 260 1.00 Runtime (min): 12.9 Injection:split Split Flow: 30 mL/min Column linear velocity: 4.21 cm/sec Column:Rtx-5 60 m × 0.32 mm × 0.25 μm

Table 2 provides the gas chromatographic results obtained from the fourβ-cyclodextrin samples. All activated charcoal containing samples showedsubstantial reduction of decomposition volatiles.

TABLE 2 Gas chromatograph SPME headspace results of β cyclodextrinpowder, dried to remove water, and heated to 290° C. for 2 minutes.Percent (%) Reduction in Activated Charcoal Gas Chromatography ThermalDecomposition Wt.-% Area Counts Products 0 12,228 NA 0.01 4,373 64.20.10 2,879 76.5 1.0 1,087 91.1

Example 4

Methyl β-cyclodextrin was analyzed for thermal stability based upon thepotential of generating volatile thermal decomposition products producedfrom impurities including include acetic acid, formic acid, furfurals,linear starches and sugars, dehydrated linear starches, levoglucosan,levoglucosenone and proteins. This method mimics the processing ofinjection molding cyclodextrin coated PET chip. A 35 wt % methylβ-cyclodextrin (degree of substitution 1.0, manufactured byWacker-Chemie of Adrian, Mich.) solution was prepared by addingβ-cyclodextrin to deionized water. Prior to preparing the solution,0.01, 0.10 and 1.0 wt % of coconut charcoal previously ground in amortar and pestle was blended into the dry cyclodextrin (16 hours @ 100°C.). Each of the three 35 wt % methyl beta cyclodextrin and activatedcharcoal solutions were centrifuged at 750 rpm for 30 minutes. An upperaliquot of the centrifuged solution, approximately 1.5 mL (1.7 g) of a35 wt % cyclodextrin solution, was added into a 40-mL headspace vialwith a Teflon-faced septa screw cap. Water was evaporated from thesolution by heating the vial using a heat gun at a moderate temperatureand gently rolling to coat the interior walls of the vial evenly whilepurging with dry nitrogen. The coated vial placed into an oven at 75° C.for approximately 10 minutes to completely solidify the cyclodextrinresidue by removing all remaining water. In some cases, the clearβ-cyclodextrin residue bubbled and hazed slightly when evaporation wascomplete. The vial with screw cap removed was heated in an oven to 290°C. for 2 minutes. The vial was removed and allowed to cool at roomtemperature for 40 seconds before applying the Teflon-faced septa screwcap. Thermal decomposition products resulting from methyl β-cyclodextrinimpurities were measured in the headspace inside the sealed vial by gaschromatography using the parameters of Table 1.

Table 3 shows the gas chromatographic results obtained from the fourmethyl β-cyclodextrin samples. All activated charcoal containing samplesshowed substantial reduction of decomposition volatiles. FIGS. 7 and 8provide the chromatographic profiles of the thermal decompositionproducts of methyl β-cyclodextrin, and methyl β-cyclodextrin containing0.1% activated carbon (based on weight of β-cyclodextrin).

TABLE 3 Gas chromatograph SPME headspace results of a 35 wt % methyl βcyclodextrin solution, dried to remove water, and heated to 290° C. for2 minutes. Percent (%) Reduction in Activated Charcoal GasChromatography Thermal Decomposition wt % Area Counts Products 0 304,903NA 0.01 141,388 53.6 0.10 84,957 72.1 1.0 71,705 76.5

Example 5

A 46.7 wt % methyl β-cyclodextrin (degree of substitution 1.0) solutionwas prepared in deionized water by adding 280 grams of methyl betacyclodextrin (dried at 100° C. for 16 hrs.) to 320 grams deionizedwater. The 600 grams of methyl β-cyclodextrin was split into two 300gram samples—Solution A and B. Solution A comprised a 46.7 wt % methylbeta cyclodextrin aqueous solution.

Coconut charcoal previously ground in a mortar and pestle was dispersedinto the Solution B at 0.280 grams. Solution B was then centrifuged at750 rpm for 30 minutes. An upper aliquot of the centrifuged solution wasused to coat the PET chip.

Both Solutions A and B were coated directly onto PET chips (Voridian PET9921W, manufactured by Eastman Chemical of Kingsport, Tenn.) having anintrinsic viscosity of 0.76+/−0.02 dl/g and density of 1.2 g/cm³ usingthe following procedure.

PET chips were coated with approximately 0.75 wt % β-cyclodextrin usingboth Solution A and Solution B. About 2.0 kg of PET resin was added toto a 4-liter wide-mouth tared bottle with TFE lined closure. The bottlewas heated to 100° C. prior to adding 8.35 g of a coating Solution A, bypouring into the center of the bottle to avoid solution contact with theglass. The coating solution weight was measured to within 0.01 gram byplacing the jar with PET chip on an analytical balance. The resin wasmixed on a rolling mixer at 30 rpm for 15 minutes to wet coat the PETchip. The cap was then removed from the upright bottle, and the bottlewas placed in a vacuum oven at 115° C. to remove the water (0.9″ Hgpressure) and set the coating on the PET chip. Three additional coatingswere made for a total of four coating. For Solution A, taking intoaccount the loss associated with coating on the bottle wall, the PETchip was found to be coated at a concentration of 0.75 wt %. The vacuumoven-dried PET chip was transferred from the bottle to the injectionmolder inline dryer and dried at normal conditions prior to injectionmolding. The bottle was reweighed to determine methyl β-cyclodextrincoating loss.

Solution ‘B’ was coated in an identical manner. The solution coated anddried chip samples Chip A (coated with Solution A), Chip B (coated withSolution B), and a control sample with no coating, Chip C, were dried ina vacuum oven at 105° C. at <0.1″ Hg. Chip A and Chip B were eachindividually blended with uncoated PET at a 1:10 ratio of coatedPET:virgin PET, producing a 750 ppm methyl β-cyclodextrin concentration.Chip B also containing 1.5 ppm activated carbon. Chips A and B in the1:10 blend with virgin PET, and Chip C were injection molded producingdog bones on a single-cavity injection-molding machine for coloranalysis. Table 4 shows the injection molding machine operatingparameters. The color of the dog bones was determined by ASTM D 6290-98using a Color-Eye 7000A spectrophotometer, and reported as the Hunter L,a and b standard units in Table 5.

TABLE 4 PET injection molding parameters. Parameter Value Extruder Temp.285° C. Mold Manifold Temp. 272° C. Mold Gate Temp. 300° C. Mold gateDia. >3 mm Screw Speed 70 rpm Screw ration 20:1 Back pressure 900 pKaCavity Fill Time 4 sec. Hold Pressure 55,000 pKa Mold Cooling Temp. 48°C.

TABLE 5 Hunter color measurements for injection molded PET samples.Sample ID Description L a b A 750 ppm methyl β-cyclodextrin 86.3 −0.889.87 B 750 ppm methyl β-cyclodextrin 90.0 −0.79 3.83 with 1.5 ppmactivated carbon C Control resin 90.9 −0.60 1.16

Table 5 shows activated carbon contained in the chip coatingsignificantly improves all Hunter color measurements. The visiblewavelength scan provided in FIG. 9 shows an improvement with theactivated carbon over the entire spectrum of visible light. Removing thethermal decomposition products produced from the impurities found methylβ-cyclodextrin during the injection molding process significantlyimproved off-color in PET and no visible impact visual clarity with theintroduction of small particle size activated carbon.

Additionally, on visual inspection of the dog bones, carbon particleswere not visible to the unaided eye. Nor were there any visible physicaldefects, such as streaking, bubbles, or the like, to indicate physicaldefects caused by the presence during processing of carbon particles orβ-cyclodextrin.

The above specification, examples and data provide a completedescription of the manufacture and use of the composition of theinvention. Since many embodiments of the invention can be made withoutdeparting from the spirit and scope of the invention, the inventionresides in the claims hereinafter appended.

1. A polymer additive composition comprising: (a) a cyclodextrin, and(b) an effective amount of carbon particles comprising activated carbon,wherein the cyclodextrin is substantially free of a compound in thecentral pore of the cyclodextrin ring.
 2. The composition of claim 1wherein the additive composition comprises a substantially uniformlyblended powder.
 3. The composition of claim 2 comprising about 0.001 toabout 1.0 wt % of carbon particles in the powder.
 4. The composition ofclaim 1 comprising about 2 to 40,000 parts by weight of cyclodextrin pereach part by weight of activated carbon particles.
 5. The composition ofclaim 1 wherein the composition further comprises a solvent.
 6. Thecomposition of claim 5 wherein the solvent is water.
 7. The compositionof claim 5 wherein the solvent is a hydrocarbon oil.
 8. The compositionof claim 5 wherein the cyclodextrin is present at about 1.8 to 60 wt %in the solvent.
 9. The composition of claim 5 wherein the activatedcarbon particles are present at about 0.001 to 1.0 wt % in the solvent.10. The composition of claim 5 wherein the composition is furtherfiltered through a filter medium having an average pore size of about 10nanometers to 100 microns.
 11. The composition of claim 10 wherein thesolvent is removed from the composition after filtering.
 12. Thecomposition of claim 5 wherein the composition is centrifuged at about500 to 1000 rpm.
 13. The composition of claim 1 wherein the carbonparticles have an average particle size of about 10 nanometers to 100microns.
 14. The composition of claim 1 wherein the carbon particlescomprise acid-washed carbon particles.
 15. The composition of claim 1wherein the cyclodextrin is β-cyclodextrin.
 16. The composition of claim1 wherein the cyclodextrin comprises a non-reducing carbohydrate.
 17. Amethod of making a masterbatch composition comprising contacting amolten reactive thermoplastic polymer with an additive mixture, theadditive mixture comprising (a) a cyclodextrin and (b) an effectiveamount of carbon particles comprising activated carbon, wherein thecyclodextrin is substantially free of a compound in the central pore ofthe cyclodextrin ring, and the reactive thermoplastic polymer comprisesa reactive group capable of reacting to form a covalent bond with thecyclodextrin.
 18. The method of claim 17 wherein the cyclodextrin iscontacted in an amount corresponding to about 100 parts by weight to150,000 parts by weight of cyclodextrin groups per each one millionparts of masterbatch composition.
 19. The method of claim 17 wherein thecyclodextrin is contacted in an amount corresponding to about 100 partsby weight to 80,000 parts by weight of cyclodextrin groups per each onemillion parts of masterbatch composition.
 20. The method of claim 17wherein the carbon particle is contacted in an amount corresponding toabout 0.005 parts by weight to 5000 parts by weight per each one millionparts of the masterbatch composition.
 21. The method of claim 17 whereinthe carbon particle is contacted in an amount corresponding to about0.05 parts by weight to 2000 parts by weight per each one million partsof the masterbatch composition.
 22. The method of claim 17 wherein thecontacting comprises extrusion blending.
 23. The method of claim 22wherein the extrusion blending is followed by the steps of: (a)extruding the masterbatch composition to form a polymeric strand; (b)passing the polymeric strand through a water bath; (c) passing thestrand through a strand cutter to form a pellet or chip; and (d) dryingthe pellet or chip.
 24. A polymer additive composition comprising: (a) asubstituted cyclodextrin compound, and (b) an effective amount of carbonparticles comprising activated carbon, wherein the substitutedcyclodextrin has a degree of substitution of about 0.3 to 2.5 and issubstantially free of a compound in the central pore of the cyclodextrinring.
 25. The composition of claim 24 comprising about 2 to 40,000 partsby weight of substituted cyclodextrin per each part by weight ofactivated carbon particles.
 26. The composition of claim 24 wherein thecomposition further comprises a solvent.
 27. The composition of claim 26wherein the solvent is water.
 28. The composition of claim 26 whereinthe solvent is a hydrocarbon oil.
 29. The composition of claim 26wherein the cyclodextrin is present at about 1.8 to 60 wt % in thesolvent.
 30. The composition of claim 26 wherein the activated carbonparticles are present at about 0.005 to 1.0 wt % in the solvent.
 31. Thecomposition of claim 24 wherein the carbon particles have an averageparticle size of about 10 nanometers to 100 microns.
 32. The compositionof claim 24 wherein the carbon particles comprise acid-washed carbonparticles.
 33. The composition of claim 24 wherein the cyclodextrincomprises β-cyclodextrin.
 34. The composition of claim 24 wherein thesubstituted cyclodextrin compound comprises a degree of substitution ofabout 0.5 to
 2. 35. The composition of claim 24 wherein the substitutedcyclodextrin comprises a non-reducing carbohydrate.
 36. The compositionof claim 24 wherein the substituted cyclodextrin compound has asubstituent substantially on at least one —OH group at the −2 or 6position of the glucose moiety in the cyclodextrin.
 37. The compositionof claim 36 wherein the cyclodextrin compound comprises a 2-O-Methylether.
 38. The composition of claim 36 wherein the cyclodextrin compoundcomprises a 6-O-Acetyl ester.
 39. The composition of claim 26 whereinthe composition is further filtered through a filter medium having anaverage pore size of about 10 nanometers to 100 microns.
 40. Thecomposition of claim 39 wherein the solvent is removed from thecomposition after filtering.
 41. The composition of claim 26 wherein thecomposition is centrifuged at about 500 to 1000 rpm.
 42. A masterbatchcomposition comprising: (a) a thermoplastic polymer; (b) a substitutedcyclodextrin compound in an amount corresponding to about 100 to 150,000parts by weight of substituted cyclodextrin per each one million partsof the composition; and (c) carbon particles comprising activated carbonin an amount corresponding to about 0.005 to 5,000 parts by weight ofcarbon particles per each one million parts of the composition, whereinthe substituted cyclodextrin has a degree of substitution of about 0.3to 2.5 and is substantially free of any compound in the central pore ofthe cyclodextrin ring.
 43. The composition of claim 42 wherein thecyclodextrin is present in an amount of about 100 parts by weight to80,000 parts by weight of the cyclodextrin compound per each one millionparts of the composition.
 44. The composition of claim 42 wherein thereare about 2 to 40,000 parts by weight of substituted cyclodextrin pereach part by weight of activated carbon particles.
 45. The compositionof claim 42 wherein the activated carbon particles are present at about0.05 to 2000 parts by weight of the carbon particles per each onemillion parts of the composition.
 46. The composition of claim 42wherein the carbon particles comprise acid washed carbon particles. 47.The composition of claim 42 wherein the cyclodextrin is β-cyclodextrin.48. The composition of claim 42 wherein the cyclodextrin compound has asubstituent substantially on at least one —OH group on the −2 or −6position of the glucose moiety in the cyclodextrin.
 49. The compositionof claim 48 wherein the cyclodextrin compound comprises a 2-O-Methylether.
 50. The composition of claim 48 wherein the cyclodextrin compoundcomprises a 6-O-Acetyl ester.
 51. The composition of claim 42 whereinthe cyclodextrin compound comprises a degree of substitution of about0.5 to
 2. 52. The composition of claim 42 wherein the activated carbonparticles have an average particle size of about 10 nanometers to 100microns.
 53. The composition of claim 42, wherein the thermoplasticpolymer is a polyamide, a polycarbonate, a polyurethane, a polyether, apolyketone, polystyrene, a polyacrylate, a polyphenylene oxide,poly(vinyl chloride), or copolymers or blends thereof.
 54. Thecomposition of claim 42 wherein the thermoplastic polymer is polyester.55. The composition of claim 54 wherein the polyester comprises at least60% by weight polyethylene terephthalate units and up to 40% by weightother polymers.
 56. The composition of claim 54 wherein the polyestercomprises at least 60 % by weight polyethylene naphthalate units and upto 40% by weight other polymers.
 57. The composition of claim 54 whereinthe polyester comprises a copolymer of polyethyleneterephthalate/isophthalate and the cyclodextrin is a non-reducingcarbohydrate.
 58. The composition of claim 61 wherein the thermoplasticpolymer is a polyolefin.
 59. The composition of claim 58 wherein thepolyolefin comprises polyethylene, polypropylene, orpoly(ethylene-co-propylene).
 60. A method of making a masterbatchcomposition, the method comprising contacting a molten thermoplasticpolymer with an additive mixture, said additive mixture comprising: (a)a substituted cyclodextrin compound in an amount corresponding to about100 parts by weight to 150,000 parts by weight of cyclodextrin groupsper each one million parts of masterbatch composition, and (b) carbonparticles comprising an activated carbon present in an amountcorresponding to about 0.005 parts by weight to 5000 parts by weight pereach one million parts of the masterbatch composition, wherein thesubstituted cyclodextrin has a degree of substitution of about 0.3 to2.5 and is substantially free of any compound in the central pore of thecyclodextrin ring.
 61. The method of claim 60 wherein the contactingcomprises extrusion blending.
 62. The method of claim 61 wherein theextrusion blending is followed by the steps of: (a) extruding themasterbatch composition to form a polymeric strand; (b) passing thepolymeric strand through a water bath; (c) passing the strand through astrand cutter to form a pellet or chip; and (d) drying the pellet orchip.
 63. The method of claim 60 wherein the cyclodextrin is present inan amount of about 200 parts by weight to 80,000 parts by weight of thecyclodextrin compound per each one million parts of the composition. 64.The method of claim 60 wherein there are about 2 to 40,000 parts byweight of substituted cyclodextrin per each part by weight of activatedcarbon particles.
 65. The method of claim 60 wherein the carbonparticles are present at about 0.05 to 2000 parts by weight of thecarbon particles per each one million parts of the composition.
 66. Themethod of claim 60 wherein the activated carbon particle has an averageparticle size of about 10 nanometers to 100 micrometers.
 67. A method ofmaking a coated pellet or chip comprising contacting an additivecomposition with the surface of a thermoplastic pellet or chip, saidadditive composition comprising: (a) a substituted cyclodextrincompound, and (b) an effective amount of carbon particles comprisingactivated carbon, wherein the substituted cyclodextrin has a degree ofsubstitution of about 0.3 to 2.5 and is substantially free of a compoundin the central pore of the cyclodextrin ring.
 68. The method of claim 67wherein the coated pellet or chip comprises about 100 parts by weight to150,000 parts by weight of the substituted cyclodextrin compound pereach one million parts of the coated pellet or chip.
 69. The method ofclaim 67 wherein the additive composition comprises about 100 to 80,000parts by weight of substituted cyclodextrin per each part by weight ofactivated carbon particles.
 70. The method of claim 67 wherein thecoated pellet or chip comprises about 0.05 to 5000 parts by weight ofcarbon particles per each one million parts of the coated pellet orchip.
 71. The method of claim 67 further comprising the step of dryingthe coated pellet or chip after coating.
 72. A thermoplastic polymericarticle comprising: (a) a thermoplastic polymer; (b) a substitutedcyclodextrin compound in an amount corresponding to about 10 parts byweight to 50,000 parts by weight of cyclodextrin groups per each onemillion parts by weight of the article; and (c) an effective amount ofcarbon particles comprising activated carbon, wherein the substitutedcyclodextrin has a degree of substitution of about 0.3 to 2.5 and issubstantially free of any compound in the central pore of thecyclodextrin ring.
 73. The article of claim 72 wherein the thermoplasticpolymer is a polyamide, a polyurethane, a polycarbonate, a polyether, apolyketone, polystyrene, a polyacrylate, a polyphenylene oxide,poly(vinyl chloride), poly(ethylene-co-vinyl alcohol), or copolymers orblends thereof.
 74. The article of claim 97 wherein the thermoplasticpolymer is a polyolefin.
 75. The article of claim 98 wherein thethermoplastic polymer is a polyester.
 76. The article of claim 75wherein the polyester comprises at least 60% by weight polyethyleneterephthalate units and up to 40% by weight other polymers.
 77. Thearticle of claim 75 wherein the polyester comprises at least 60% byweight polyethylene naphthalate units and up to 40% by weight otherpolymers.
 78. The article of claim 72 wherein the cyclodextrin isβ-cyclodextrin.
 79. The article of claim 72 wherein the cyclodextrincompound has a substituent substantially on at least one —OH group onthe −2 or −6 position of the glucose moiety in the cyclodextrin.
 80. Thearticle of claim 79 wherein the cyclodextrin compound comprises a2-O-Methyl ether.
 81. The article of claim 79 wherein the cyclodextrincompound comprises a 6-O-Acetyl ester.
 82. The article of claim 72wherein the cyclodextrin compound comprises a degree of substitution ofabout 0.5 to
 2. 83. The article of claim 72 wherein the cyclodextrin ispresent in an amount of about 100 parts by weight to 25,000 parts byweight per each one million parts of polymer.
 84. The article of claim72 wherein there are about 2 to 40,000 parts by weight of substitutedcyclodextrin per each part by weight of activated carbon particles. 85.The article of claim 72 wherein the activated carbon particles arepresent at about 0.001 to 500 parts by weight of the carbon particlesper each one million parts of the article.
 86. The article of claim 72wherein the activated carbon particles are present at about 0.05 to 100parts by weight of the carbon particles per each one million parts ofthe article.
 87. The article of claim 72 wherein the activated carbonparticles have an average particle size of about 10 nanometers to 500nanometers.
 88. The article of claim 72 wherein the carbon particlescomprise acid washed carbon particles.
 89. The article of claim 72wherein the article comprises a parison or a preform.
 90. The article ofclaim 72 wherein the article comprises a finished article.
 91. Thearticle of claim 90 wherein the finished article comprises a container,a closure, a film, a coextruded film, a sheet, a liner, a semi-rigidmember, a rigid member, a shaped member, a molded member, an embossedmember, a porous member, a fiber, a yarn, a nonwoven fabric, a wovenfabric, a coating on an article, a thin layer on top of an article, athick layer on top of an article, a barrier layer, an injection moldedarticle, a blow molded article, a rotomolded article, masterbatchpellets, an open-celled foam, a closed-cell foam, an adhesive article,an absorbent article, or a portion or a combination thereof.
 92. Thearticle of claim 73 wherein the thermoplastic polymeric composition hasno substantial visible polymer defects nor any substantial discolorationcaused by the carbon particles and no carbon particles visible to theunaided human eye.
 93. The article of claim 73 wherein the thermoplasticpolymeric composition has substantially the same stress-strainproperties as the thermoplastic polymer without the substitutedcyclodextrin and without the carbon particles.
 94. A method of making athermoplastic article comprising the steps of: (a) contacting a treatedthermoplastic chip or pellet with an untreated thermoplastic chip orpellet, the treated thermoplastic chip or pellet comprising (i) asubstituted cyclodextrin in an amount of about 100 parts by weight to150,000 parts by weight of per each one million parts of the treatedchip, and (ii) a carbon particle comprising an activated carbon in anamount of 0.005 to 5000 parts by weight per one million parts of thetreated chip; and (b) forming the article, wherein the substitutedcyclodextrin has a degree of substitution of about 0.3 to 2.5 and issubstantially free of any compound in the central pore of thecyclodextrin ring.
 95. The method of claim 94 wherein the additivetreatment is present substantially on the surface of the treated chip.96. The method of claim 94 wherein the additive treatment is presentsubstantially uniformly throughout the treated chip.
 97. The method ofclaim 94 wherein one part by weight of the treated thermoplasticpolymeric chip or pellet is blended with about 1 to 40 parts by weightof untreated thermoplastic polymeric chip or pellet.
 98. A method ofmaking a thermoplastic article comprising the steps of (a) contacting athermoplastic polymer with an additive composition, the additivecomposition comprising (i) a substituted cyclodextrin and (ii) aneffective amount of carbon particles comprising an activated carbon; and(b) forming said article, wherein the substituted cyclodextrin has adegree of substitution of about 0.3 to 2.5 and is substantially free ofany compound in the central pore of the cyclodextrin ring.
 99. A polymeradditive composition comprising: (a) a functionalized polymer comprisinga cyclodextrin covalently bonded to a polymer, and (b) an effectiveamount of carbon particles comprising activated carbon, wherein thecyclodextrin is substantially free of a compound in the central pore ofthe cyclodextrin ring.
 100. The composition of claim 99 wherein thereare about 2 to 40,000 parts by weight of cyclodextrin groups per eachpart by weight of activated carbon particles.
 101. The composition ofclaim 99 wherein the composition further comprises a solvent.
 102. Thecomposition of claim 99 further comprising an oil.
 103. The compositionof claim 101 wherein cyclodextrin groups are present at about 1.8 to 60wt % in the solvent.
 104. The composition of claim 101 wherein theactivated carbon particles are present at about 0.001 to 1.0 wt % in thesolvent.
 105. The composition of claim 99 wherein the carbon particleshave an average particle size of about 10 nanometers to 100 microns.106. The composition of claim 99 wherein the carbon particles compriseacid washed carbon particles.
 107. The composition of claim 99 whereinthe cyclodextrin is β-cyclodextrin.
 108. The composition of claim 99wherein the cyclodextrin further comprises a substituent substantiallyon at least one —OH group at the −2 or 6 position of the glucose moietyin the cyclodextrin.
 109. The composition of claim 108 wherein thesubstituent comprises a 2-O-Methyl ether.
 110. The composition of claim108 wherein the substituent comprises a 6-O-Acetyl ester.
 111. Thecomposition of claim 99 wherein the cyclodextrin is integrally situatedwithin the polymer backbone of the functionalized polymer.
 112. Thecomposition of claim 99 wherein the cyclodextrin is pendant to thepolymer backbone of the functionalized polymer.
 113. The composition ofclaim 99 wherein the functionalized polymer comprises a polyamide, apolycarbonate, a polyurethane, a polyether, a polyketone, polystyrene, apolyacrylate, a polyphenylene oxide, poly(vinyl chloride),poly(ethylene-co-vinyl alcohol), or copolymers or blends thereof. 114.The composition of claim 99 wherein the functionalized polymer is apolyolefin.
 115. The composition of claim 114 wherein the polyolefincomprises a polyethylene, a polypropylene, a polyisobutene, or apoly(ethylene-co-propylene).
 116. The composition of claim 111 whereinthe cyclodextrin is grafted to the polymer through a reaction with ananhydride moiety, an epoxide moiety, or a chloride moiety.
 117. Thecomposition of claim 116 wherein the cyclodextrin is grafted to thepolymer through an anhydride moiety comprising maleic anhydride.
 118. Amasterbatch composition comprising: (a) a thermoplastic polymer; (b) afunctionalized polymer comprising a cyclodextrin group covalently bondedto a polymer, in an amount corresponding to about 100 to 150,000 partsby weight of cyclodextrin groups per each one million parts of thecomposition; and (c) a carbon particle comprising an activated carbon,in an amount corresponding to about 0.005 to 5,000 parts by weight ofcarbon particles per each one million parts of the composition, whereinthe cyclodextrin is substantially free of a compound in the central poreof the cyclodextrin ring.
 119. The composition of claim 118 wherein thecyclodextrin group is β-cyclodextrin.
 120. The composition of claim 118wherein the cyclodextrin group further has a substituent substantiallyon at least one —OH group on the −2 or −6 position of the glucose moietyin the cyclodextrin.
 121. The composition of claim 120 wherein thesubstituent comprises a 2-O-Methyl ether.
 122. The composition of claim120 wherein the substituent comprises a 6-O-Acetyl ester.
 123. Thecomposition of claim 118 wherein the cyclodextrin is present in anamount of about 100 parts by weight to 80,000 parts by weight of thecyclodextrin compound per each one million parts of the composition.124. The composition of claim 118 wherein there are about 2 to 40,000parts by weight of substituted cyclodextrin per each part by weight ofactivated carbon particles.
 125. The composition of claim 118 whereinthe activated carbon particles are present at about 0.05 to 2000 partsby weight of the carbon particles per each one million parts of thecomposition.
 126. The composition of claim 118 wherein the activatedcarbon particles have an average particle size of about 10 nanometers to100 microns.
 127. The composition of claim 118 wherein the carbonparticles comprise acid washed carbon particles.
 128. The composition ofclaim 118 wherein the thermoplastic polymer is a polyamide, apolycarbonate, a polyurethane, a polyether, a polyketone, polystyrene, apolyacrylate, a polyphenylene oxide, poly(vinyl chloride), or copolymersor blends thereof.
 129. The composition of claim 118 wherein thethermoplastic polymer is polyester.
 130. The composition of claim 118wherein the thermoplastic polymer is a polyolefin.
 131. The compositionof claim 118 wherein the functionalized polymer comprises a polymercomprising a polyester, a polyamide, a polycarbonate, a polyurethane, apolyether, a polyketone, polystyrene, a polyacrylate, a polyphenyleneoxide, or copolymers or blends thereof.
 132. The composition of claim118 wherein the functionalized polymer comprises a polyolefin.
 133. Thecomposition of claim 132 wherein the polyolefin comprises apolyethylene, a polypropylene, a polyisobutylene, apoly(ethylene-co-propylene), or copolymers or blends thereof.
 134. Thecomposition of claim 118 wherein the cyclodextrin is integrally situatedin the polymer backbone of the functionalized polymer.
 135. Thecomposition of claim 118 wherein the cyclodextrin is pendant from thepolymer backbone of the functionalized polymer.
 136. A method of makinga masterbatch composition, the method comprising contacting a moltenthermoplastic polymer with an additive mixture, the additive mixturecomprising (a) a functionalized polymer comprising a cyclodextrin groupcovalently bonded to a polymer, and (b) a carbon particle comprising anactivated carbon, wherein the cyclodextrin groups are substantially freeof a compound in the central pore of the cyclodextrin ring, thefunctionalized polymer is present in an amount corresponding to about100 parts by weight to 150,000 parts by weight of cyclodextrin groupsper each one million parts of polymeric composition, and the carbonparticle is present in an amount corresponding to about 0.005 parts byweight to 5000 parts by weight per each one million parts of thepolymeric composition.
 137. A method of making a masterbatchcomposition, the method comprising contacting an additive composition tothe surface of a thermoplastic pellet or chip, said additive compositioncomprising: (a) a functionalized polymer comprising a cyclodextrin groupcovalently bonded to a polymer and added in an amount corresponding toabout 100 parts by weight to 150,000 parts by weight of cyclodextringroups per each one million parts of polymeric composition, and (b) acarbon particle comprising an activated carbon, added in an amountcorresponding to about 0.005 parts by weight to 5000 parts by weight ofcarbon particles per each one million parts of the polymericcomposition, wherein the cyclodextrin groups are substantially free of acompound in the central pore of the cyclodextrin ring.
 138. Athermoplastic article comprising: (a) a thermoplastic polymer; (b) afunctionalized polymer comprising a cyclodextrin group covalently bondedto a polymer, added in an amount corresponding to about 10 parts byweight to 50,000 parts by weight of cyclodextrin groups per each onemillion parts by weight of the article and (c) an effective amount ofcarbon particles comprising activated carbon, wherein the cyclodextringroup is substantially free of any compound in the central pore of thecyclodextrin ring.
 139. The article of claim 138 wherein thethermoplastic polymer is a polyester, a polyamide, a polyurethane, apolycarbonate, a polyether, a polyketone, polystyrene, a polyacrylate, apolyphenylene oxide, poly(vinyl chloride), or copolymers or blendsthereof.
 140. The article of claim 138 wherein the thermoplastic polymeris a polyolefin.
 141. The article of claim 140 wherein the polyolefincomprises a polyethylene, a polypropylene, apoly(ethylene-co-propylene), a polybutylene, or a copolymer or blendthereof.
 142. The article of claim 138 wherein the cyclodextrin group isβ-cyclodextrin.
 143. The article of claim 138 wherein the cyclodextringroup is further substituted substantially on at least one —OH group onthe −2 or −6 position of the glucose moiety in the cyclodextrin group.144. The article of claim 143 wherein the cyclodextrin group comprises a2-O-Methyl ether.
 145. The article of claim 143 wherein the cyclodextringroup comprises a 6-O-Acetyl ester.
 146. The article of claim 138wherein the cyclodextrin group comprises a degree of substitution ofabout 0.3 to 2.5.
 147. The article of claim 138 wherein the cyclodextringroups are present in an amount of about 100 parts by weight to 25,000parts by weight per each one million parts of the article.
 148. Thearticle of claim 138 wherein there are about 2 to 40,000 parts by weightof substituted cyclodextrin per each part by weight of activated carbonparticles.
 149. The article of claim 138 wherein the activated carbonparticles are present at about 0.05 to 100 parts by weight of the carbonparticles per each one million parts of the article.
 150. The article ofclaim 138 wherein the activated carbon particles have an averageparticle size of about 10 nanometers to 500 nanometers.
 151. The articleof claim 138 wherein the carbon particles comprise acid washed carbonparticles.
 152. The article of claim 138 wherein the polymericcomposition comprises a parison or a preform.
 153. The article of claim138 wherein the polymeric composition comprises a finished articlecomprising a container, a closure, a film, a coextruded film, a sheet, aliner, a semi-rigid member, a rigid member, a shaped member, a moldedmember, an embossed member, a porous member, a fiber, a yam, a nonwovenfabric, a woven fabric, a coating on an article, a thin layer on top ofan article, a thick layer on top of an article, a barrier layer, aninjection molded article, a blow molded article, a rotomolded article,masterbatch pellets, an open-celled foam, a closed-cell foam, anadhesive article, an absorbent article, or a portion or a combinationthereof.
 154. The article of claim 138 wherein the article has nosubstantial visible defects nor substantial discoloration due to carbonparticles and no carbon particles visible to the unaided human eye. 155.The article of claim 138 wherein the article has substantially the sametensile properties as the thermoplastic polymer without the substitutedcyclodextrin and without the carbon particles.
 156. The article of claim138 wherein the functionalized polymer comprises a polymer comprising apolyester, a polyamide, a polycarbonate, a polyurethane, a polyether, apolyketone, polystyrene, a polyacrylate, a polyphenylene oxide,poly(vinyl chloride), or copolymers or blends thereof.
 157. The articleof claim 138 wherein the functionalized polymer comprises a polyolefin.158. The article of claim 138 wherein the cyclodextrin groups areintegrally situated within the backbone of the functionalized polymer.159. The article of claim 138 wherein the cyclodextrin is pendant to thebackbone of the functionalized polymer.
 160. The article of claim 159wherein the cyclodextrin is bonded to the polymer through a reactionwith an anhydride moiety, an epoxide moiety, or a chloride moiety. 161.The article of claim 160 wherein the cyclodextrin is grafted to thepolymer through a reaction with an anhydride moiety comprising maleicanhydride.
 162. A method of making a thermoplastic polymeric articlecomprising the steps of: (a) melt blending a treated thermoplasticpolymeric chip or pellet and an untreated thermoplastic chip or pellet,said treated thermoplastic polymeric chip or pellet comprising anadditive treatment comprising (i) a functionalized polymer comprising acyclodextrin group covalently bonded to a polymer, the cyclodextringrafted polymer being present in an amount of about 100 parts by weightto 150,000 parts by weight of per each one million parts of the treatedchip, and (ii) carbon particles comprising an activated carbon, presentin the in an amount of 0.005 to 5000 parts by weight per one millionparts of the treated chip; and (b) forming the article, wherein thecyclodextrin groups are substantially free of any compound in thecentral pore of the cyclodextrin ring, wherein the cyclodextrin groupsare present in an amount of about 10 to 50,000 parts by weight per onemillion parts by weight of the article and the carbon particles arepresent in an amount of about 0.001 to 500 parts by weight per millionparts of the article.
 163. The method of claim 162 wherein the meltblending is carried out in an extruder.
 164. The article of claim 162wherein forming the article comprises injection molding, blow molding,injection blow molding, melt blowing, electrospinning, solution coating,film extrusion, film coextrusion, profile extrusion, extrusion coating,or a combination thereof.
 165. The method of claim 162 wherein thewherein there are about 2 to 40,000 parts by weight of cyclodextringroups per each part by weight of activated carbon particles.
 166. Themethod of claim 162 wherein the carbon particles are present at about0.05 to 100 parts by weight per each one million parts by weight of thearticle.
 167. The method of claim 162, wherein the carbon particles arepresent at about 0.05 to 50 parts by weight per each one million partsby weight of the article.
 168. The method of claim 162 wherein theadditive treatment is present substantially on the surface of thetreated chip.
 169. The method of claim 162 wherein the additivetreatment is present substantially uniformly throughout the treatedchip.
 170. The method of claim 162 wherein one part by weight of thetreated thermoplastic polymeric chip or pellet is blended with about 1to 40 parts by weight of untreated thermoplastic chip or pellet.
 171. Amethod of making a thermoplastic article comprising the steps of: (a)blending a molten thermoplastic polymer with an additive composition,the additive composition comprising (i) a functionalized polymercomprising a cyclodextrin group covalently bonded to a polymer, and (ii)a carbon particle comprising an activated carbon; and (b) forming thearticle, wherein the cyclodextrin groups are substantially free of anycompound in the central pore of the cyclodextrin ring, wherein thecyclodextrin groups are present an amount of about 10 to 50,000 parts byweight per one million parts by weight of the article and the carbonparticle is present in an amount of about 0.001 to 500 parts by weightper million parts by weight of the article.
 172. The method of claim 171wherein the blending is carried out in an extruder.
 173. The method ofclaim 171 wherein forming the article comprises injection molding, blowmolding, injection blow molding, melt blowing, electrospinning, solutioncoating, film extrusion, film coextrusion, profile extrusion, extrusioncoating, or a combination thereof.
 174. The method of claim 7 1, whereinthe wherein there are about 2 to 40,000 parts by weight of cyclodextringroups per each part by weight of activated carbon particles.
 175. Themethod of claim 171 wherein the carbon particles are present at about0.05 to 100 parts by weight per each one million parts by weight of thearticle.